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Microfluidic mixing has significant applications in various fields, including materials synthesis and biochemical analysis. In this study, we propose a universal strategy to enhance mixing efficiency in microfluidic chips. This strategy initially divides the liquid into branches, which then converge in an interdigitated manner at the beginning of the mixing segment. This branch-convergence structure reduces the flow width of each liquid, thereby decreasing the diffusion distances required for mixing. Under the conditions of this study, the mixing efficiency could be improved by approximately 10 times. Importantly, this enhancement strategy only requires changing the structure of the liquid inflow channel without changing the structure of the mixing segment. Thus, this strategy has broad applicability, any mixing section with different principles and structures can be connected downstream of the branch-convergence structure. In addition, we applied this universal mixing enhancement strategy to the continuous synthesis of lactic- co -glycolic acid nanoparticles, resulting in a higher uniformity of synthesized nanoparticles compared to unenhanced devices.

Secondary pollution remains a critical challenge for the catalytic destruction of chlorinated volatile organic compounds (CVOCs). By employing experimental studies and theoretical calculations, we provide valuable insights into the catalytic behaviors exhibited by ceria rods, cubes, and octahedra for monochloromethane (MCM) destruction, shedding light on the elementary reactions over facet-dependent CeO 2 . Our findings demonstrate that CeO 2 nanorods with the (110) facet exhibit the best performance in MCM destruction, and the role of vacancies is mainly to form a longer distance (4.63 Å) of frustrated Lewis pairs (FLPs) compared to the stoichiometric surface, thereby enhancing the activation of MCM molecules. Subsequent molecular orbital analysis showed that the adsorption of MCM mainly transferred electrons from the 3 σ and 4 π * orbitals to the Ce 4f orbitals, and the activation was mainly caused by weakening of the 3 σ bonding orbitals. Furthermore, isotopic experiments and theoretical calculations demonstrated that the hydrogen chloride generated is mainly derived from methyl in MCM rather than from water, and the primary function of water is to form excess saturated H on the surface, facilitating the desorption of generated hydrogen chloride.

The conventional V 2 O 5 -WO 3 /TiO 2 catalyst suffers severely from arsenic poisoning, leading to a significant loss of catalytic activity. The doping of Al or Mo plays an important role in promoting the arsenic resistance on NH 3 selective catalytic reduction (NH 3 -SCR), but their promotion mechanism remains in debate and has yet to be explored in multipollutant control (MPC) of NO x and chlorinated organics. Herein, our experimental characterizations and density functional theory (DFT) calculations confirmed that arsenic species preferentially adsorb on both Al and Mo to form arsenate, thereby avoiding bonding to the catalytically active V sites. More importantly, Al doping partially converted the polymeric vanadyl species into monomeric ones, thereby inhibiting the near-surface and bulk lattice oxygen mobility of the V 2 O 5 -WO 3 /TiO 2 catalyst, while Mo doping resulted in vanadyl polymerization with an enriched V 5+ chemical state and exhibited superior MPC activity and CO x selectivity. Our work shows that antipoisoning catalysts can be designed with the combination of site protection and occurrence state modification of the active species.

Ru-based catalysts have been extensively employed for the catalytic destruction of chlorinated volatile organic compounds (VOCs), but their versatility for other routine VOCs' destruction has been less explored. Herein, we show that Ru-decorated SnO 2 /CeO 2 mixed oxides can sustain H 2 O and HCl poisonings and are endowed with extraordinary versatility for a wide range of VOCs' destruction. Selective adsorption of Ru on the cassiterite SnO 2 and CeO 2 nanorods through a Coulomb force can rationally tune the oxidation and dechlorination centers on decorated catalysts, where the epitaxial growth of RuO x on top of SnO 2 is endowed with excellent dechlorination ability and that on CeO 2 is functional as an oxidation center; the latter could also activate H 2 O to provide sufficient H protons for HCl formation. Our developed Ru/SnO 2 /CeO 2 catalyst can steadily destruct mono-chlorobenzene, ortho-dichlorobenzene, trichloroethylene, dichloromethane, epichlorohydrin, N -hexane, ethyl acetate, toluene, and their mixtures at an optimum temperature of 300 °C, and its monolithic form is also functional at this temperature with few dioxins being detected in the off-gas. Our results imply that the Ru-decorated SnO 2 /CeO 2 catalyst can meet the demands of regenerative catalytic oxidation for the treatment of a wide range of VOCs from industrial exhausts.

Objective: Photodynamic therapy (PDT) triggers various cellular responses and induces cell death via necrosis and/or apoptosis. This study evaluated the feasibility of using O2 and Ca(2+) fluxes as indicators of apoptosis induced by rose bengal (RB)-mediated PDT in human oral squamous carcinoma cells (Cal27 cells)., Methods: Intracellular reactive oxygen species (ROS) generation was assessed by the dichloro-dihydro-fluorescein diacetate (DCFH-DA) method. Real-time O2 and Ca(2+) flux measurements were performed using the noninvasive micro-test technique (NMT). Apoptosis of the PDT-treated cells was confirmed by 4'6-diamidino-2-phenylindole-dilactate staining. The activation of apoptosis-related molecules was examined using Western blot. We assayed the effects of the fluctuation of O2 and Ca(2+) flux in response to PDT and the apoptotic mechanism, by which ROS, O2, and Ca(2+) synergistically may trigger apoptosis in PDT-treated cells., Results: Real-time O2 and Ca(2+) flux measurements revealed that these indicators were involved in the timely regulation of apoptosis in the PDT-treated cells and were activated 2 h after PDT treatment. RB-mediated PDT significantly elicited the generation of ROS by approximately threefold, which was critical for PDT-induced apoptosis. Cytochrome c and cleaved caspase-3, caspase-9 and poly ADP ribose polymerase (PARP) were overexpressed, and the data provided evidence that 2 h was considered to be the key observation time in RB-mediated PDT-induced apoptosis in Cal27 cells., Conclusions: Our collective results indicated that the effects of O2 and Ca(2+) fluxes may act as a real-time biomonitoring system of apoptosis in the RB-PDT-treated cells. Also, RB-mediated PDT can be a potential and effective therapeutic modality in oral squamous cell carcinoma.

Objective: To investigate the expression of programmed death-1 (PD-1) and programmed death ligand-1(PD-L1) in peripheral T-lymphocytes from patients with chronic periodontitis and its significance and to clarify its role in the development of chronic periodontitis., Methods: A total of 73 subjects were included in the study and divided into three groups, chronic periodontitis(30 cases), chronic gingivitis(25 cases) and 18 healthy controls. The peripheral blood was collected and PD-1/PD-L1 expression in the surface of CD(+)4 T lymphocytes and CD(+)8 T lymphocytes was examined by flow cytometry. Blood samples from 16 chronic periodontitis patients were collected at week 0 and 6 after initial therapy for 6 weeks and PD-1 and PD-L1 expression in the surface of CD(+)4 and CD(+)8 T lymphocytes was also determined by flow cytometry. The data were statistically analyzed., Results: The percentage of PD-1 expression in CD(+)4 and CD(+)8 T lymphocytes of chronic periodontitis group[(16.7 ± 5.5)%,(20.8 ± 5.1)%]and chronic gingivitis group[(14.2 ± 6.1)%,(14.5 ± 4.3)%]were higher than that of healthy controls[(9.5 ± 2.1)%, (8.1 ± 1.9)%](P < 0.05). The percentage of PD-L1 expression in CD(+)4 and CD(+)8 T lymphocytes of chronic periodontitis group[(24.2 ± 7.1)%,(15.3 ± 6.8)%]and chronic gingivitis group[(12.4 ± 6.0)%,(11.2 ± 5.5)%]were higher than that of healthy controls[(4.7 ± 1.2)%, (3.2 ± 2.3)%] (P < 0.05). The percentage of PD-1/PD-L1 expression in CD(+)4 T lymphocytes and CD(+)8 T lymphocytes of the chronic periodontitis group were significantly decreased after initial therapy(P < 0.05)., Conclusions: The expression of PD-1 and PD-L1 in peripheral CD(+)4 T lymphocytes and CD(+)8 T lymphocyte of chronic periodontitis patients was up-regulated and was associated with periodontal condition. The initial therapy reduced the expression of PD-1 and PD-L1.