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Chemical bonds created between cations and oxygen ions perform a critical role in the oxygen permeability of perovskite oxides. Here, fluorine was doped into the O-sites of perovskite to weaken metal-oxygen bonds and successfully synthesize Ba0.5Sr0.5Co0.8Fe0.17Y0.03O3-δF0.09 oxides. The crystal structure, morphology, and oxygen permeability of the Ba0.5Sr0.5Co0.8Fe0.17Y0.03O3-δF0.09 oxides were investigated. The results indicated that partial substitution of oxygen ions with those of fluorine greatly enhanced the oxygen permeation flux. Both thermogravimetric analysis and O2-TPD results indicated that more O2 escaped from F-doped perovskite and more oxygen vacancies were generated. The O 1s XPS spectra showed that the lower metal-oxygen bond energy was responsible for the improved oxygen permeability of F-doped perovskite. Oxygen permeation flux reached 3.15 ml min−1 cm−2 at 900 °C and was maintained at approximately 3 ml min−1 cm−2 for 1300 h in the oxygen permeation test. A membrane reactor equipped with an F-doped disc membrane was constructed to produce syngas, reaching 99% methane conversion and an 88% carbon monoxide selectivity at 900 °C.

Background: TAILORx data confirm that using Oncotype DX (ODX) to assess the risk of early-stage breast cancer recurrence can spare women unnecessary chemotherapy. However, high up-front costs (list price, $4175) could dissuade usage. Also, from a technical perspective, this test cannot be widely used in developing countries, especially in relatively poor areas. Methods: By analyzing the Surveillance, Epidemiology, and End-Results database, multinomial ordinal logistic regression, random forest, gradient boosting decision tree, extreme gradient boosting, and multi-layer perceptron were adopted to develop an assistant forecast system for recurrence risk—low to intermediate (RS=2–25) or high (RS=26–100)—based on individuals’ sociodemographic and clinicopathological information. We validated the system using an independent dataset (training-test split of the original dataset) as validation. Results: We identified 111,635 patients with breast cancer: 86,617 patients (77.59%) were aged 50 years or younger; 23,514 patients (21.1%) had low risk scores, 71,439 patients (64.0%) had intermediate risk scores, and 16,682 patients (14.9%) had high risk scores. Variables closely associated (all P

Background: Immunotherapy, especially immune-checkpoint inhibitors (PD-1 and PD-L1 inhibitors), is now one of the mainstays of cancer treatment. Several studies have analyzed treatment-related toxicities of immunotherapy. However, small sample size, rough and unspecific stratification, and lack of comparison (pure sing-arm studies) are common limitations. Detailed organ- and system-specific toxicities remain not clear enough. Methods: We systematically searched PubMed, Embase, Cochrane Library, Web of Science and others (CNKI), from database inception to Mar 31, 2020, for randomized controlled trials (RCTs) related to PD-1/PD-L1 inhibitors that had available toxicity data. We excluded non-randomized trials. The primary endpoint was to assess the difference in the incidences of toxicities between cancer patients who did and did not receive PD-1/PD-L1 inhibitors. We calculated the pooled relative risks (RRs) and corresponding 95% confidence intervals (95% CIs) using a random-effects model and assessed the heterogeneity between different groups. The subgroup analyses were conducted based on toxicity grade (severity), system and organ, treatment regimens in the intervention arm and control arm, PD-1/PD-L1 inhibitor drug type, and cancer histotype. We applied the five-point Jadad ranking system to evaluate the quality of the selected studies. We performed multivariate meta-regression analyses to explore the proportion of between-study variance. Findings: A total of 29 eligible RCTs including 8067 patients were selected for the meta-analysis based on specified inclusion and exclusion criteria. Patients treated with PD-1/PD-L1 inhibitors were at lower risks of overall toxicities (all grades: RR 0.91, 95% CI 0.89-0.92; grade 3~4: RR 0.76, 95% CI 0.74-0.78), including gastrointestinal toxicity (all grades: RR 0.68, 95% CI 0.60-0.77; grade 3~4: RR 0.71, 95% CI 0.43-1.20), hematologic toxicity (all grades: RR 0.66, 95% CI 0.51-0.85; grade 3~4: RR 0.55, 95% CI 0.37-0.83), and treatment event leading to discontinuation (all grades: RR 0.78, 95% CI 0.72-0.84; grade 3~4: RR 0.58, 95% CI 0.49-0.67); but were at higher risks for respiratory toxicity (all grades: RR 1.74, 95% CI 1.33-2.28; grade 3~4: RR 1.92, 95% CI 1.45-2.55) and endocrine toxicity (all grades: RR 1.70, 95% CI 0.62-4.69; grade 3~4: RR 1.29, 95% CI 0.45-3.69). The subgroup analyses indicated that when compared with the control, toxicity comparison tendency for PD-1/PD-L1 inhibitors varied with the toxicity grade, affected system and organ, treatment regimens in the intervention arm and control arm, drug type, and cancer histotype. The male-female ratio was a statistically significant variable in the Meta-Regression analysis (I2=89.1, τ2=0.01, and P=0.001). Interpretation: For most toxicity types based on system and organ, the incidence proportions for patients in the intervention arm were lower than those in the control arm, which suggested the general safety of PD-1/PD-L1 inhibitors against conventional chemotherapy and CTLA-4 inhibitors. However, for some specific toxicities including respiratory, cutaneous, and endocrine toxicities, the case was the opposite. The toxicity grade, system and organ, treatment regimens, drug type, and cancer histotype were all influencing factors. To our knowledge, this was by far the most comprehensive meta-analysis of RCTs on toxicities of immune-checkpoint inhibitors. Future research should focus on taking effective targeted measures to decrease the risks of different toxicities for different patient populations. Funding Statement: This work was supported by the Beijing Municipal Natural Science Foundation (No. 7204293 and No. 19G10077), the Special Research Fund for Central Universities, Peking Union Medical College (No. 3332019053), the Beijing Hope Run Special Fund of Cancer Foundation of China (No. LC2019B03 and No. LC2019L07), the Natural Science Foundation of China (No. 81872160), and National Key R&D Program of China (No. 2018YFC1315000 and No. 2018YFC1315003). The funders have no conflicts of interests. Declaration of Interests: The authors declare no conflict of interest. Ethics Approval Statement: The analysis followed the Strengthening the Reporting of observational Studies in Epidemiology (STROBE) guidelines. National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College institutional review board approved this study as exempt.

Newborns are highly susceptible to DNA virus infections, which may result from the characteristics of neonatal innate immune systems. Here we analyzed for the first time the development of innate immune sensing and signaling of intracellular DNA virus infection in human newborns and young children. Both mRNA and protein expression of cGAS, an intracellular DNA sensor, were shown to be significantly reduced in neonatal peripheral blood mononuclear cells (PBMCs). In addition, cGAS expression in neonatal PBMCs could be induced upon herpes simplex virus type 1 (HSV-1) or interferon-α (IFNα) stimulation. Furthermore, production of the second messenger cGAMP and activation of the transcriptional factor IRF3 was severely decreased in neonatal cord blood mononuclear cells (CBMCs) or PBMCs compared with adults. In contrast, the downstream signaling STING-TBK1-IRF3 appeared to be functional in neonatal PBMCs, as demonstrated by the fact that IRF3 phosphorylation and IFNβ production in these cells could be activated by cGAMP. Intriguingly, decreased expression of cGAS in neonatal cells can be rescued by DNA demethylation, with concomitant enhancement in IFNβ induction by HSV-1. Thus, cGAS restoration or STING stimulation by small molecules during infancy might improve the age-dependent susceptibility to DNA virus infection.

Graphene membranes have shown promising prospects in cations separation; however, the underlying separation mechanisms remain elusive. In this study, the permeation of five cations through graphene membranes with variable pore size and surface charge density is explored by molecular simulations. It reveals that negatively charged graphene draws cations closer to the membrane. While positively charged graphene together with small-sized pores generates larger energy barriers, promoting the separation of different cation pairs. Result shows that the separation mechanisms are dominated by electrostatic interaction and steric hindrance. This theoretical work could guide the design of graphene membrane for desalination.

The characteristics of velocity gradient jumping discontinuity are studied in pipe flow of a Johnson–Segalman fluid model, which allows for the non-monotonic relationship between the shear stress and velocity gradient in a simple shear flow for a certain domain range of the material parameters, including slip parameter , Weissenberg number and ratio of viscosities . This non-monotonic constitutive equation admitting multiple steady-state solutions is characterized by shear rate discontinuities. Firstly, the analytical solutions of critical maximum pressure gradient and minimum pressure gradient are calculated with material parameters. Then the properties of “ top jumping ” and “ bottom jumping ” of velocity gradient, which are introduced by increasing and decreasing of pressure gradient respectively, and their relation with spurt phenomena, are investigated in this paper. We find that the non-overlapping processes of velocity gradient “ top jumping ” and “ bottom jumping ” are in analogy to the variation process for amplitude/frequency relationship in non-linear vibration mechanics. It means two jumping processes cannot occur in the same way of pressure gradient increasing or decreasing. This exploring point is distinctly different from the present literatures. And we have made a confirmation that the flow would be subdivided into two layers when velocity gradient jumping happens in the processes of pressure gradient increasing and pressure gradient decreasing in steady flow. Especially the effects of the velocity gradient jumping on the flow rate are considered quantitatively. Besides, there is a linear relationship between pressure gradient and shear stress. However the varying process of velocity gradient is characterized by jumping discontinuities between two critical pressure gradients. Additionally, the effects of material parameters on the top jumping and bottom jumping locations have been considered to find out where the spurt phenomena occur. Finally, the flow rates in different processes of pressure gradient increasing and pressure gradient decreasing have been discussed to provide potential opportunity for practical application in industrial transportation.

The density functional theory (DFT) was applied to investigate the adsorption and growth of Ptn (n = 1–4) clusters and hydrogen spillover on γ-Al2O3 surface, which is of importance for many catalysis reactions. It was found that the growth ability of the supported Ptn cluster is weaker than the gas phase Ptn clusters. Basin structures on both of the clean and hydrated surfaces were found to stabilize the Pt clusters. For the hydrated surface, the basin structure, together with the size of Ptn cluster, was also found to take trivial impacts on the hydrogen spillover. The most feasible supplier of H species on the hydrated γ-Al2O3 surface was identified. Additionally, it was interesting to found that there would be an optimized size of the supported Ptn cluster at n > 3.

Exact solutions of shear stress versus velocity gradient and the numerical solutions of streamwise velocity distribution in radial direction of a Johnson–Segalman fluid in a circular pipe are obtained. The effects of material parameters, Weissenberg number, ratio of viscosities and slip parameter, on shear stress and streamwise velocity have been considered to investigate the discontinuous velocity derivatives and stick-slip phenomenon at the wall. We find that there is a non-monotonic relationship between the shear stress and rate of shear for certain values of the material parameters and consequently, the velocity profile has discontinuous derivatives. Also the non-monotonic region is shortening with the increasing of ratio of viscosities, and is lengthening with the increasing of slip parameter. For the flow with larger slip parameter, the initially driving pressure gradient has to be larger for the appearance of spurt phenomenon. Moreover, the variational range of material parameters is given for the appearance of a non-monotonic relationship between the shear stress and the rate of shear. Finally, we have shown the exact expression of critical pressure gradient and also have given the conditions where spurt phenomena occur.

The eigenvalue problems are considered for the fractional ordinary differential equations with different classes of boundary conditions including the Dirichlet, Neumann, Robin boundary conditions and the periodic boundary condition. The eigenvalues and eigenfunctions are characterized in terms of the Mittag–Leffler functions. The eigenvalues of several specified boundary value problems are calculated by using MATLAB subroutine for the Mittag–Leffler functions. When the order is taken as the value 2, our results degenerate to the classical ones of the second-ordered differential equations. When the order α satisfies 1

A new general Jacobi elliptic function expansion algorithm is developed to obtain exact solutions for discrete nonlinear systems. Applying this method, many exact Jabobi elliptic function travelling wave solutions for Ablowitz–Ladik discrete nonlinear Schrodinger system are derived. These doubly periodic solutions may degenerate to hyperbolic function solutions including discrete soliton solutions as the modulus m → 1 and trigonometric function solutions as m → 0, respectively.

Lagrangian and Eulerian statistics were obtained from the direct numerical simulation of a turbulent channel flow. The Eulerian integral time scales and time microscales were compared to their Lagrangian equivalents. It is found that the Lagrangian time scales equal the Eulerian time scales at the wall. Otherwise, these proved to be consistently larger than the Eulerian time scales, and the latter are also found to be scaled by the propagation velocity rather than the mean velocity. The near-wall behavior of the ratio of the Lagrangian to Eulerian integral time scales is explained by the difference between the mean velocity and the propagation velocity of the turbulent structure. The ratio is proportional to the inverse of the turbulence intensity ( T L / T E = βU / σ ). β for the streamwise component is nearly a constant value of 0.6 (20 y + y + > 40). After period over the integral time scale elapsed, the effect of shear on turbulent diffusion appears and the mean-square dispersion is almost proportional to t 3 in agreement with the predictions of Riley and Corrsin [The relation of turbulent diffusivities to Lagrangian velocity statistics for the simplest shear flow. J. Geophys. Res. 79 (1974) 1768–1771] for homogeneous shear flow. After particles are distributed fairly uniformly between two walls, the mean-square dispersion becomes proportional to t and in agreement with theory of Taylor’s longitudinal dispersion.

A general solution including three arbitrary functions is obtained for the (2 + 1)-dimensional high-order Broer–Kaup equation by means of WTC truncation method. From the general solution, doubly periodic wave solutions in terms of the Jacobian elliptic functions with different modulus and folded solitary wave solutions determined by appropriate multiple valued functions are obtained. Some interesting novel features and interaction properties of these exact solutions and coherent localized structures are revealed.