Copper-based nanodots as efficient biomimetic antibiotics for the treatment of oral bacterial infections Author links open overlay panel

Oral infectious diseases caused by a variety of pathogenic bacteria seriously affect the quality of life.However,these diseases remain a clinical challenge because of the lack of simple,safe,and universal prophylactics.To address these limitations,we synthesize CuO_(x)nanodots(CuO_(x)NDs)with excellent Fenton-like reaction activity and utilize them in the treatment of oral bacterial infections.Different from other complicated approaches,CuO_(x)NDs are rationally prepared using a facile one-pot aqueous synthesis.In the presence of H_(2)O_(2),these well-developed CuO_(x)NDs can efficiently catalyze the generation of hydroxyl radicals(·OH)around oral pathogens,leading to the death of various bacteria.Meanwhile,results of biosafety indicate the high biocompatibility and extremely low toxicity of these CuO_(x)NDs.After understanding the admirable in vitro antibacterial effect of CuO_(x)NDs in the presence of H_(2)O_(2),we further explore their in vivo antibacterial performance on several classical animal models including oral mucosal wound model,intragingival bacteria-infected model,and the periodontal infection model.As expected,these CuO_(x)NDs with wide-spectrum antibacterial activity can serve as high-performance antibacterial reagents for the treatment of various oral bacterial infections with the help of H_(2)O_(2).In brief,current nanoplatform can act as efficient antibiotics against oral pathogens with broadening the biomedical applications of copper-based nanomaterials.

Direct amplification of femtosecond optical vortices in a single-crystal fiber

Spatially twisted light with femtosecond temporal structure is of particular interest in strong-field physics and light–matter interactions.However,present femtosecond vortex sources exhibit limited power handling capabilities,and their amplification remains an ongoing challenge particularly for high-order orbital angular momentum(OAM)states due to several inherent technical difficulties.Here,we exploit a straightforward approach to directly amplify a femtosecond optical vortex(FOV,OAM=-8?)by using a two-stage single-crystal fiber(SCF)amplifier system without pulse stretching and compression in the time domain,delivering 23-W,163-fs pulses at a repetition rate of1 MHz.The spatial and temporal features are well-conserved during the amplification,as well as the high modal purity(>96%).The results indicate that the multi-stage SCF amplifier system is particularly suited for direct amplification of high-order FOVs.The generated high-power femtosecond OAM laser beams are expected to help reveal complex physical phenomena in light–matter interactions and pave the way for practical applications in attoscience,laser plasma acceleration,and high-dimension micromachining.

Widely tunable 2μm optical vortex from a Tm:YAP laser

In this paper,we report on a wide wavelength tuning optical vortex carrying orbital angular momentum(OAM)of±?,from a thulium-doped yttrium aluminum perovskite(YAP)laser employing a birefringent filter.The OAM is experimentally found to be well maintained during the whole wavelength tuning process.The Laguerre-Gaussian(LG_(0,+1))mode with a tuning range of 58 nm from 1934.8 to 1993.0 nm and LG0,-1mode with a range of 76 nm from 1920.4 to 1996.6 nm,are,respectively,obtained.This is,to the best of our knowledge,the first experimental implementation of wavelength tuning for a scalar vortex laser in the 2μm spectral range,as well as the broadest tuning range ever reported from the vortex laser cavity.Such a vortex laser with robust structure and straightforward wavelength tuning capability will be an ideal light source for potential applications in the field of optical communication with one additional degree of freedom.

面心立方金属中非共格孪晶界原子结构的孪晶厚度效应研究

非共格孪晶界(ITB)能显著影响金属力学性能,受到了研究者极大关注.理论模型预测ITB是由系列偏位错组成,ITB两侧的晶面没有沿[111]方向的相对位移.本文利用分子静力学模拟研究了Ag,Cu,Ni和Al中ITB的结构,发现ITB的结构具有显著的尺寸效应.对于较薄的ITB,界面两侧的晶面处于同一水平面,没有沿[111]方向的相对位移,与理论模型结果一致.而对于较厚的ITB,界面两侧的晶面有明显的[111]方向的相对位移,且相对位移随着ITB厚度的增加而增加.此外,研究揭示出ITB两侧晶面沿[111]方向的位移与金属的层错能直接相关.该研究表明ITB的结构并不唯一,不同的厚度、层错能对应不同的ITB结构.本研究为理解孪晶厚度和层错能对金属力学性能的影响提供了新见解.