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The bacterial accumulation at the margins of dental resin composites is a main cause of secondary caries, which may further lead to prosthodontic failure. In this regard, this study for the first time incorporated 2D MXene Ti3C2Tx nanosheets (NSs) into epoxy resin at different mass ratios (0, 0.5, 1.0, and 2.0 wt%) by solution blending and direct curing for dental applications. Compared to the pure resin, the as-fabricated MXene/resin composite not only exhibited improved mechanical and abrasive results but also displayed gradually improved antibacterial activity with MXene loading which was further enhanced by illumination in natural light due to the high photothermal efficiency of MXene. In addition, the cytotoxicity result demonstrated that the MXene-modified resin did not cause severe damage to normal cells. This novel MXene/resin nanocomposite could pave the way for new designs for high-performance, multifunctional nanocomposites to effectively protect dental health in daily life.

Copper (Cu)-based materials are widely used in many fields from industry to life, including marine, medical apparatus and instruments, and microelectronic devices owing to their superior thermal, electrical, and mechanical properties. However, the interaction of copper with aggressive and fouling liquids under normal circumstances easily brings about severe bacterial accumulation, resulting in undesirable functionality degeneration and bacterial infections. In this contribution, we reported a novel copper-based sponge, polydimethylsiloxane (PDMS)@graphdiyne (GDY)@Cu, constructed by in situ synthesis of GDY on a commercial Cu sponge, followed by the modification of PDMS. The as-fabricated PDMS@GDY@Cu sponge not only possesses excellent self-cleaning activity against the pollution of daily drinks and dirt due to an improved static contact angle (~136°), but also display a remarkably enhanced anticorrosion performance, attributed to intimate coverage of chemically stable GDY and PDMS on the Cu sponge. Based on high photothermal effect of GDY, the PDMS@GDY@Cu sponge also displays significantly improved antibacterial activities under irradiation. In addition, due to excellent chemical stability of PDMS and GDY, self-cleaning behavior and photothermal-assisted antibacterial performance are well maintained after long-term attack of bacteria. These results demonstrate that GDY-based functional coatings hold great promises in the protection of copper devices under harsh conditions.

Bismuth (Bi) has achieved remarkable progress due to its intriguing physicochemical properties, such as low toxicity, controllable stability, tunable bandgap, superior optical response, and strong diamagnetism. Bi-based hybrids have drawn increasing attention in recent years due to the integrated features of the Bi component and the synergistic effect on the separation and transfer of charges, holding great promises for versatile applications. In this Perspective, we systematically review the recent progress on the controlled synthesis of Bi-based heterostructures and their improved nanophotonic performances compared with those of mono-element Bi counterparts and present the existing challenges and future opportunities. It is anticipated that this Perspective can shed light on new designs of high-performance functional Bi-based heterostructures to meet the growing demand for next-generation nanophotonic systems.

In recent years, tin monosulfide (SnS), one kind of black phosphorus analogues, is of great interest owing to its unique properties, such as low cost, environmental compatibility, nontoxicity, earth‐abundance, etc., which merit it an ideal candidate for modern devices, such as batteries, sensors, and optoelectronics, among others. The controllable and precise synthesis of SnS‐based nanostructures with various crystal phases, sizes, and compositions holds great potential for high‐performance devices as crucial components. To further improve their performance for next‐generation devices, the nanoengineering of SnS‐based nanostructures has been extensively explored over the past decade. In this review, the latest research and progress on SnS‐based nanostructures, including 0D, 1D, 2D, and 3D pure SnS nanostructures, and SnS‐based loaded, sandwiched or encapsulated models are comprehensively presented, focusing on their synthetic approaches, fundamental properties, and fascinating applications such as batteries and solar cells, catalysis (photocatalysis and electrocatalysis), optoelectronics, sensors, ferroelectrics, thermoelectrics, nonlinear properties, and biomedical applications. Finally, the critical challenges and constructive perspectives are discussed for further improvement of the SnS‐based nanostructures in these burgeoning fields.

In the oral microenvironment, bacteria colonies are easily aggregated on the tooth-restoration surface, in the manner of a biofilm, which usually consists of heterogeneous structures containing clusters of a variety of bacteria embedded in an extracellular matrix, leading to serious recurrent caries. In this contribution, zero-dimensional (0D) bismuth (Bi) quantum dots (QDs) synthesized by a facile solvothermal method were directly employed to fabricate a Bi QD/polydimethylsiloxane (PDMS)-modified tooth by simple curing treatment. The result demonstrates that the as-fabricated Bi QD/PDMS-modified tooth at 37 °C for 120 min not only showed significantly improved hydrophobic performance with a water contact angle of 103° and 115° on the tooth root and tooth crown, respectively, compared to that (~20° on the tooth root, and ~5° on the tooth crown) of the pristine tooth, but also exhibited excellent antibacterial activity against S. mutans, superior biocompatibility, and biosafety. In addition, due to the highly photothermal effect of Bi QDs, the antibacterial activity of the as-fabricated Bi QD/PDMS-modified tooth could be further enhanced under illumination, even at a very low power density (12 mW cm−2). Due to the facile fabrication, excellent hydrophobicity, superior antibacterial activity, and biocompatibility and biosafety of the Bi QD/PDMS-modified tooth, it is envisioned that the Bi QD/PDMS-modified tooth with a fascinating self-cleaning and antibacterial performance can pave the way to new designs of versatile multifunctional nanocomposites to prevent secondary caries in the application of dental restoration.

Tin oxide (SnO2) nanomaterials are of great interest in many fields such as catalytic, electrochemical, and biomedical applications, due to their low cost, suitable stability characteristics, high photosensitivity, etc. In this contribution, SnO2 NPs were facilely fabricated by calcination of tin (II) oxalate in air, followed by a liquid-phase exfoliation (LPE) method. Size-selected SnO2 NPs were easily obtained using a liquid cascade centrifugation (LCC) technique. The as-obtained SnO2 NPs displayed strong absorption in the UV region (~300 nm) and exhibited narrower absorption characteristics with a decrease in NP size. The as-fabricated SnO2 NPs were, for the first time, directly deposited onto a poly(ethylene terephthalate) (PET) film with a regular Ag lattice to fabricate a flexible working electrode for a photoelectrochemical (PEC)-type photodetector. The results demonstrated that the SnO2-NP-based electrode showed the strongest photoresponse signal in an alkaline electrolyte compared with those in neutral and acidic electrolytes. The maximum photocurrent density reached 14.0 μA cm−2, significantly outperforming black phosphorus nanosheets and black phosphorus analogue nanomaterials such as tin (II) sulfide nanosheets and tellurene. The as-fabricated SnO2 NPs with relatively larger size had better self-powered photoresponse performance. In addition, the as-fabricated SnO2-NP-based PEC photodetector exhibited strong cycling stability for on/off switching behavior under ambient conditions. It is anticipated that SnO2 nanostructures, as building blocks, can offer diverse availabilities for high-performance self-powered optoelectronic devices to realize a carbon-neutral or carbon-free environment.

Over the past decade, Q-switched fiber lasers have drawn extensive attention in nonlinear frequency conversion, industrial material processing, bioscience, spectroscopy, etc., due to their cost-effectiveness, robustness, and compactness. However, the widely employed passive Q-switching easily suffers from the degradation of saturable absorbers under intracavity pulse irradiation and the inaccurate modification of the repetition rate, leading to a large barrier for their practical applications. To this end, an all-optical modulator (AOM) is rationally designed based on the superior photothermal conversion of two-dimensional (2D) graphdiyne (GDY) in this work for an actively Q-switched fiber laser. The developed AOM based on a Michelson interferometer composed of few-layer 2D GDY nanosheets exhibits tunable output parameters (e.g., intensity and phase modulation), high stability, and easy synchronization due to the high photothermal effect of 2D GDY and is successfully applied into all-optical signal processing with reliable transmission of ASCII codes ("N", "T", and "U"). Additionally, an actively Q-switched laser is also constructed by the 2D GDY-based AOM, which demonstrates that the developed active AOM processes all-optically tunable output parameters, precise synchronization, and environmental robustness. It is expected that this prototypical active 2D GDY-based AOM with multiple features (superior photothermal conversion, satisfactory energy consumption, and large modulation depth) can provide fundamental guidance on designs of advanced all-optical information processing and all-optical communication networks. [ABSTRACT FROM AUTHOR]

AIM: To summarize the implementation effect of comprehensive prevention and treatment service model for diabetic ophthalmopathy in Pudong New Area, and provide practical reference for the establishment and improvement of the community-based comprehensive prevention and treatment service model of diabetic ophthalmopathy.METHODS: From 2018-08 to 2019-08, diabetes patients with chronic disease management were selected for screening in the 45 community of Pudong New Area, stratified sampling by age and sex. The eye health data of long-distance screening were analyzed, and master the degree of satisfaction and participation willingness through the questionnaire survey.RESULTS: The screening included 39 055 patients with DM, all of whom established eye health files for the first time. 15.870%(6 198/39 055)was made a definite diagnosis preliminarily of diabetic retinopathy, the prevalence of mild, moderate, severe NPDR and PDR were 3.974%, 9.904%, 1.746% and 0.246% respectively. The rate of needing referral was 44.325%(17 311/39 055); the rate of actual follow-up was 5.846%(1 012/17 311); the satisfaction of DR screening and willingness to participate were over 85%.CONCLUSION: The service mode of comprehensive prevention and treatment for diabetic ophthalmopathy based on remote screening system was feasible for early detection, early diagnosis and early intervention of diabetic ophthalmopathy, but it needs further optimization and improvement in practice application.

The fungal plasma membrane H+-ATPase (Pma1) pumps protons out of the cell to maintain the transmembrane electrochemical gradient and membrane potential. As an essential P-type ATPase uniquely found in fungi and plants, Pma1 is an attractive antifungal drug target. Two recent Cryo-EM studies on Pma1 have revealed its hexameric architecture, autoinhibitory and activation mechanisms, and proton transport mechanism. These structures provide new perspectives for the development of antifungal drugs targeting Pma1. In this article, we review the history of Pma1 structure determination, the latest structural insights into Pma1, and drug discoveries targeting Pma1. [ABSTRACT FROM AUTHOR]

Investigating the correlation between structural diversity and functionality serves as a pivotal factor in propelling the progress of functional materials, which however commonly needs tedious synthesis or sophisticated screening of conditions. Herein, we establish a facile strategy to synthesize two series of coordination networks (CNs, i.e., Ln-CMNDI and LN-CMNDI-F) with two distinct topologies using a solvent-directed method employing a specific ligand N,N′-bis(carboxymethyl)-1,4,5,8-naphthalenediimide (H2CMNDI) and rare-earth metal ions. The single-crystal X-ray diffraction analysis shows that Ln-CMNDI-F (Ln = La, Pr, Sm, Tb, Dy, Eu, Yb) synthesized using DMF and H2O as the solvents adopt a two-dimensional planar structure, while Ln-CMNDI (Ln= Ho, Gd, Tb, Yb, La and Eu) with three-dimensional supramolecular structures are obtained under the same conditions due to the existence of hydrogen bonding between molecules when DMF is replaced with DMA. The topology type of Ln-CMNDI-F is assigned as lcf (abbreviation of Ln-CMNDI-F) and the topological type of Ln-CMNDI is assigned as lcn (abbreviation of Ln-CMNDI) which are both not collected in the RCSR. Moreover, such differences in the changes of the topological structures lead to different optical properties including photochromism properties and fluorescence sensing abilities. The photochromism property of Ln-CMNDI-F is superior to that of Ln-CMNDI in terms of the speed of photoresponse. However, Ln-CMNDI exhibits a better performance in fluorescence sensing towards nitrophenols. This work reveals that Ln-CMNDI and Ln-CMNDI-F with novel topological structures can be constructed by adjusting the solvent reasonably, providing insights for the construction of CNs with promising optical applications. [ABSTRACT FROM AUTHOR]