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Abstract Background Highly active anti-retroviral therapy (HAART) can successfully suppress human immunodeficiency virus (HIV) viral replication and reconstruct immune function reconstruction in HIV-1-infected patients. However, about 15–30% of HIV-1-infected patients still fail to recover their CD4+ T cell counts after HAART treatment, which means immune reconstruction failure. Pyroptosis plays an important role in the death of CD4+ T cells in HIV-1- infected patients. The study aims to explore the association between the expression of pyroptosis in peripheral blood and immune function reconstruction in HIV-1- infected patients. Methods One hundred thirty-five HIV-1-infected patients including immunological non-responders (INR) group, immunological responders (IR) group and normal immune function control (NC) group were analyzed. The expression of GSDMD and Caspase-1 in peripheral blood of HIV-1-infected patients were measured by qPCR. The concentrations of GSDMD, Caspase-1, IL-1β and IL-18 in the peripheral serum were quantified by ELISA. The associations between the expression of pyroptosis in peripheral blood and immune function reconstruction were analyzed using multivariate logistic models. Results The relative expression of GSDMD mRNA and caspase-1 mRNA in peripheral blood, as well as the expression of IL-18 cytokine in the INR, were significantly higher than those in the IR and NC (P 0.05). Multivariate logistic analysis showed that the patients with baseline CD4+ T cell counts less than 100 cells/μL (aOR 7.051, 95% CI 1.115–44.592, P = 0.038), high level of expression of Caspase-1mRNA (aOR 2.803, 95% CI 1.065–7.377, P = 0.037) and IL-18 cytokine (aOR 10.131, 95% CI 1.616–63.505, P = 0.013) had significant poor CD4+ T cell recovery. Conclusions The baseline CD4+ T cell counts less than 100 cells/μL, high relative expression of Caspase-1 mRNA, and high expression of IL-18 cytokine are associated factors that affect the reconstruction of immune function.

Selective conversion of methane into value-added chemicals is a promising approach for utilization of hydrocarbon sources. Here the authors develop dimeric copper centers supported on graphitic carbon nitride (denoted as Cu2@C3N4) with >10% conversion and >98% selectivity toward methyl oxygenates in both thermo- and photo- catalytic reactions.

Two–electron (2e-) oxygen reduction reaction (ORR) shows great promise for on–site electrochemical synthesis of hydrogen peroxide (H2O2). However, it is still a great challenge to design efficient electrocatalysts for H2O2 synthesis. To address this issue, the logical design of the active site by controlling the geometric and electronic structures is urgently desired. Therefore, using density functional theory (DFT) computations, two kinds of hybrid double–atom supported on C2N nanosheet (RuCu@C2N and PdCu@C2N) are screened out and their H2O2 performances are predicted. PdCu@C2N exhibits higher activity for H2O2 synthesis with a lower overpotential of 0.12 V than RuCu@C2N (0.59 V), Ru3Cu(110) facet (0.60 V), and PdCu(110) facet (0.54 V). In aqueous phase, the adsorbed O2 is further stabilized with bulk H2O and the thermodynamic rate–determining step of 2e- ORR change. The activation barrier on PdCu@C2N is 0.43 eV lower than the one on RuCu@C2N with 0.68 eV. PdCu@C2N is near the top of 2e- ORR volcano plot, and exhibits high selectivity of H2O2. This work provides guidelines for designing highly effective hybrid double–atom electrocatalysts (HDACs) for H2O2 synthesis.

Highlights A standalone-like smart device that can remotely track the variation of air pollutants in a power-saving way is created; Metal–organic framework-derived hollow polyhedral ZnO was successfully synthesized, allowing the created smart device to be highly selective and to sensitively track the variation of NO2 concentration; A novel photoluminescence-enhanced Li-Fi telecommunication technique is proposed, offering the created smart device with the capability of long distance wireless communication. Abstract Remote tracking the variation of air quality in an effective way will be highly helpful to decrease the health risk of human short- and long-term exposures to air pollution. However, high power consumption and poor sensing performance remain the concerned issues, thereby limiting the scale-up in deploying air quality tracking networks. Herein, we report a standalone-like smart device that can remotely track the variation of air pollutants in a power-saving way. Brevity, the created smart device demonstrated satisfactory selectivity (against six kinds of representative exhaust gases or air pollutants), desirable response magnitude (164–100 ppm), and acceptable response/recovery rate (52.0/50.5 s), as well as linear response relationship to NO2. After aging for 2 weeks, the created device exhibited relatively stable sensing performance more than 3 months. Moreover, a photoluminescence-enhanced light fidelity (Li-Fi) telecommunication technique is proposed and the Li-Fi communication distance is significantly extended. Conclusively, our reported standalone-like smart device would sever as a powerful sensing platform to construct high-performance and low-power consumption air quality wireless sensor networks and to prevent air pollutant-induced diseases via a more effective and low-cost approach.

Catalytic performance of supported metal catalysts not only depends on the reactivity of metal, but also the adsorption and diffusion properties of gas molecules which are usually affected by many factors, such as temperature, pressure, properties of metal clusters and substrates, etc. To explore the impact of each of these macroscopic factors, we simulated the movement of CO molecules confined in graphene nanoslits with or without supported Pt nanoparticles. The results of molecular dynamics simulations show that the diffusion of gas molecules is accelerated with high temperature, low pressure or low surface-atom number of supported metals. Notably, the supported metal nanoparticles greatly affect the gas diffusion due to the adsorption of gas molecules. Furthermore, to bridge a quantitative relationship between microscopic simulation and macroscopic properties, a generalized formula is derived from the simulation data to calculate the diffusion coefficient. This work helps to advise the diffusion modulation of gas molecules via structural design of catalysts and regulation of reaction conditions.

High-performance tracking trace amounts of NO2 with gas sensors could be helpful in protecting human health since high levels of NO2 may increase the risk of developing acute exacerbation of chronic obstructive pulmonary disease. Among various gas sensors, Graphene-based sensors have attracted broad attention due to their sensitivity, particularly with the addition of noble metals (e.g., Ag). Nevertheless, the internal mechanism of improving the gas sensing behavior through doping Ag is still unclear. Herein, the impact of Ag doping on the sensing properties of Graphene-based sensors is systematically analyzed via first principles. Based on the density-functional theory (DFT), the adsorption behavior of specific gases (NO2, NH3, H2O, CO2, CH4, and C2H6) on Ag-doped Graphene (Ag–Gr) is calculated and compared. It is found that NO2 shows the strongest interaction and largest Mulliken charge transfer to Ag–Gr among these studied gases, which may directly result in the highest sensitivity toward NO2 for the Ag–Gr-based gas sensor.

Nanoscale tailoring the filler morphology in experiment offers new opportunities to modulate the mechanical properties of polymer nanocomposites. Based on the conventical rod and experimentally available tetrapod filler, I compare the nanofiller dispersion and elastic moduli of these two kinds of nanocomposites via molecular dynamics simulation and a lattice spring model. The results show that the tetrapod has better dispersion than the rod, which is facilitate forming the percolation network and thus benefitting the mechanical reinforcement. The elastic modulus of tetrapod filled nanocomposites is much higher than those filled with rod, and the modulus disparity strongly depends on the aspect ratio of fillers and particle-polymer interaction, which agrees well with experimental results. From the stress distribution analysis on single particles, it is concluded that the mechanical disparity between bare rod and tetrapod filled composites is due to the effective stress transfer in the polymer/tetrapod composites.