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The nonlinear optical properties of silicon have great potentials for developing all-optical switches and modulators, etc. Strategies based on all dielectric silicon photonic crystals and resonators have been proposed to design the nanophotonic devices with high nonlinearity. Nevertheless, the lack of compatible configuration with the mature CMOS technology may hinder the practical applications of the all dielectric devices. In this work, we proposed a metal–silicon hybrid metasurface to generate strong third harmonic signals from an amorphous silicon (α-Si) film. By integrating the α-Si film into a gold plasmonic nanocavity and controlling the periods of the gold meta-atoms, the efficiency of the THG process is expected to be greatly boosted. Compared to the planar α-Si film, the THG signal is enhanced by a factor of ∼370. The presented results in this work may open new routes for developing various silicon photonic devices with high optical nonlinearity.

In linear optical processes, compact and effective wavefront shaping techniques have been developed with the artificially engineered materials and devices in the past decades. Recently, wavefront shaping of light at newly generated frequencies was also demonstrated using nonlinear photonic crystals and metasurfaces. However, the nonlinear wave-shaping devices with both high nonlinear optical efficiency and high wave shaping efficiency are difficult to realize. To circumvent this constraint, we propose the idea of metasurface decorated optical crystal to take the best aspects of both traditional nonlinear crystals and photonic metasurfaces. In the proof-of-concept experiment, we show that a silicon nitride metasurface decorated quartz crystal can be used for the wavefront shaping of the second harmonic waves generated in quartz. With this crystal-metasurface hybrid platform, the nonlinear vortex beam generation and nonlinear holography were successfully demonstrated. The proposed methodology may have important applications in nonlinear structured light generation, super-resolution imaging, and optical information processing, etc.

Microplastics are a growing concern as pollutants that impact both public health and the environment. However, the toxic effects of polypropylene microplastics (PP‐MPs) are not well understood. This study aimed to investigate the effects of PP‐MPs on cardiotoxicity and its underlying mechanisms. The cardiotoxicity of exposure to different amounts of PP‐MPs were investigated in both ICR mice and H9C2 cells. Our results demonstrated that sub‐chronic exposure to 5 and 50 mg/L PP‐MPs led to myocardial structural damage, apoptosis, and fibrosis in mice cardiomyocytes. Flow cytometry analysis revealed that PP‐MPs could decrease mitochondrial membrane potential and induce apoptosis in H9C2 cells. Western blotting revealed decreased expression of Bcl‐2, poly(ADP‐ribose) polymerase (PARP) and caspase 3 and increased expression of Bax, cleaved‐PARP, and cleaved‐caspase 3 in PP‐MPs‐treated cardiac tissue and H9C2 cells. These results confirmed the apoptotic effects induced by PP‐MPs. Moreover, PP‐MPs treatment triggered oxidative stress, as evidenced by the increased levels of malondialdehyde; reduction in glutathione peroxidase, superoxide dismutase, and catalase activities in mice cardiac tissues; and increased reactive oxygen species levels in H9C2 cells. Finally, western blotting demonstrated that exposure to PP‐MPs significantly reduced the expression levels of Nrf2 and p‐ERK proteins associated with MAPK‐Nrf2 pathway in both cardiac tissue and H9C2 cells. Overall, our findings indicate that PP‐MPs can induce cardiomyocyte apoptosis through MAPK‐Nrf2 signaling pathway, which is triggered by oxidative stress. This study provides a foundation for determining the effects of PP‐MPs on cardiotoxicity and their underlying mechanisms. [ABSTRACT FROM AUTHOR]

BackgroundAcquired resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) will eventually occur in almost all advanced EGFR-mutant non-small cell lung cancer (EGFR-mutant NSCLC) patients although the therapy has been a standard treatment for such patients. But EGFR-TKIs in combination with anti-angiogenic drugsmay prolong the survival time of these patients.ObjectiveTo explore the efficacy and safety of EGFR-TKIs with anti-angiogenic drugs as the treatment for patients with advanced EGFR-mutant NSCLC.MethodsDatabases including CNKI, CQVIP, Wanfang Data Knowledge Service Platform, PubMed, EMBase, and The Cochrane Library were searched from inception to July 2021 using subject headings with free-text words, for randomized controlled trials (RCTs) about the first-line treatment of advanced EGFR-mutant NSCLC patients with EGFR-TKIs in combination with anti-angiogenic drugs (combination therapy group) versus EGFR-TKIs alone (monotherapy group) . Two researchers performed literature screening, data extraction (the first author, publication time, the country where the author coming from, study type, sample size, stage of NSCLC, sex, average age, treatment regimen, ECOG PS score, median follow-up time, pathological type, gene mutation type, outcome indicators) , separately, and assessed risk of bias in the included RCTs. STATA 15.0 was used formeta-analysis.ResultsNine RCTs were included, involving 1 553 patients. Meta-analysis results showed that the combination therapy was associated with longer progression-free survival (PFS) 〔HR=0.61, 95%CI (0.54, 0.70) , P0.05) . Moreover, the combination therapy was not superior to monotherapy in terms of prolonging the overall survival, and improving the objective response rate, and disease control rate (P>0.05) . However, the rate of adverse eventsabove grade 3〔RR=1.77, 95%CI (1.62, 1.94) , P

The introduction of enlarged and interconnected nanochannels into metal–organic frameworks (MOFs) overcome their micropore size restriction, enhances mass transportation, and improves the accessibility of anchored metal clusters. Herein, foamed Ce‐MOF single crystals (F‐Ce‐MOF‐SC‐x) designed from a multiscale co‐assembly is reported in the presence of a copolymer template and 1,3,5‐trimethylbenzene as a structural regulator. The resultant F‐Ce‐MOF‐SC‐x possessed well‐defined microporous tandem‐ordered meso‐macroporous foams with superior connectivity and versatile Ce‐defective unsaturated sites (Ce‐DUS). F‐Ce‐MOF‐SC‐x is applied as a stable carrier for anchoring polytertiary amines (PA) via coordination interactions with Ce‐DUS. Owing to the superior ability of PA to recognize SO2, the resultant F‐Ce‐MOF‐SC‐x@yPA delivers exceptional performance in terms of the high‐temperature reversible adsorption and separation of SO2, including a remarkable capacity for SO2, spectacular selectivity for SO2/CO2/N2, an ultrafast adsorption equilibrium rate, and stability for 50 cycles. These characteristics are outstanding among those of MOFs and superior to those of many reported SO2 adsorbents. [ABSTRACT FROM AUTHOR]

In linear optical processes, compact and effective wavefront shaping techniques have been developed with the artificially engineered materials and devices in the past decades. Recently, wavefront shaping of light at newly generated frequencies was also demonstrated using nonlinear photonic crystals and metasurfaces. However, the nonlinear wave-shaping devices with both high nonlinear optical efficiency and high wave shaping efficiency are difficult to realize. To circumvent this constraint, we propose the idea of metasurface decorated optical crystal to take the best aspects of both traditional nonlinear crystals and photonic metasurfaces. In the proof-of-concept experiment, we show that a silicon nitride metasurface decorated quartz crystal can be used for the wavefront shaping of the second harmonic waves generated in quartz. With this crystal-metasurface hybrid platform, the nonlinear vortex beam generation and nonlinear holography were successfully demonstrated. The proposed methodology may have important applications in nonlinear structured light generation, super-resolution imaging, and optical information processing, etc. [ABSTRACT FROM AUTHOR]

Herein, a variety of 2,6-diaminopyridine (DAP) derived nitrogen-doped hierarchically porous carbon (DAP-NHPC-T) prepared from carbonization-induced structure transformation of DAP-Zn-SiO 2 -P123 nanocomposites are reported, which are facilely prepared from solvent-free co-assembly of block copolymer templates P123 with pyridine-rich monomer of DAP, Zn(NO 3 ) 2 and tetramethoxysilane. In the pyrolysis process, P123 and SiO 2 templates promote the formation of mesoporous and supermicroporous structures in the DAP-NHPC-T, while high-temperature volatilization of Zn contributed to generation of micropores. The DAP-NHPC-T possess large BET surface areas (≈956-1126 m 2  g -1 ), hierarchical porosity with micro-supermicro-mesoporous feature and high nitrogen contents (≈10.44-5.99 at%) with tunable density of pyridine-based nitrogen sites (≈5.99-3.32 at%), exhibiting good accessibility and reinforced interaction with SO 2 . Consequently, the DAP-NHPC-T show high SO 2 capacity (14.7 mmol g -1 , 25 °C and 1.0 bar) and SO 2 /CO 2 /N 2 IAST selectivities, extraordinary dynamic breakthrough separation efficiency and cycling stability, far beyond any other reported nitrogen-doped metal-free carbon. As verified by in situ spectroscopy and theoretical calculations, the pyridine-based nitrogen sites of the DAP-NHPC-T boost SO 2 adsorption via the unique charge transfer, the adsorption mechanism and reaction model have been finally clarified., (© 2024 Wiley‐VCH GmbH.)

As a highly toxic and corrosive waste gas in the industry, hydrogen sulfide (H 2 S) usually originates from the utilization of coal, petroleum, and natural gas. The selective catalytic elimination of H 2 S shows great significance to ensure the safety of industrial processes and health of human beings. Herein, we report efficiently selective oxidation of H 2 S to elemental sulfur over covalent triazine framework (CTF-1- x , x = 400, 500, 600, 400-600 °C) catalysts. CTF-1- x samples were prepared from polymerization of 1,4-dicyanobenzene to form polyaryl triazine networks under ion solidothermal conditions in the presence of ZnCl 2 , which acts as both an initiator and a porogen. The resultant CTF-1- x samples possess abundant micro-mesoporosity, large Brunauer-Emmett-Teller (BET) surface areas, and tunable structural base sites with edge amine and graphitic nitrogen characteristics, which were homogeneously decorated onto their frameworks. As a result, CTF-1- x samples act as efficient and long-lived catalysts in selective oxidation of H 2 S to sulfur under ambient conditions (100% H 2 S conversion, 100% sulfur selectivity at 180 °C, 12 000 mL/(g·h)), and their activities were superior to those of commercial Fe 2 O 3 and g-C 3 N 4 desulfurization catalysts. Abundant nitrogen structural base sites of CTF-1- x effectively activate the reactants, and abundant micro-mesoporosity facilitates mass transfer in and out of CTF-1- x . The improved design of the nitrogen-doped carbon material for H 2 S activation and conversion could enhance the development of more active and robust nitrogen-doped carbon catalysts.