Energy‐level modulation between perovskite and carrier transport layers to obtain a promoted carrier extraction and reduced charge recombination is an effective way to achieve high‐efficiency ...perovskite solar cells. Here, diboron is used as an effective interfacial modifier between SnO2 and perovskite. By taking advantage of the higher Fermi level on the surface of SnO2 after diboron treatment, a power‐conversion efficiency of 22.04% in a solar cell device based on two‐step solution‐processed planar n‐i‐p structure is obtained. With the help of thorough characterizations, it is argued that the diboron‐treated SnO2 exhibits some Sn3+ species, which serve as electron donors with a more n‐type nature, promoting electron extraction and reducing carrier recombination in the electron transport layer (ETL)/perovskite interface. Further analysis speculates that the formation of surface diboron–oxygen Lewis pair induces a reducing state of diboron complexes, resulting in the spontaneous electron redistribution and the formation of Sn3+−O–• species. This provides an effective chemical approach to tune the energy alignment between the oxide ETL and absorber.
Diboron‐treated SnO2 exhibits some Sn3+ species, which serve as electron donors with more n‐type nature, resulting in the higher Fermi level on the surface of SnO2, promoting electron extraction and reducing carrier recombination in the electron transport layer (ETL)/perovskite interface. A power‐conversion efficiency of 22.04% is obtained in an n‐i‐p structure perovskite solar cell.
An electrochemical aptasensor based on aptamer was designed for the first time to simultaneously detect Cd
and Pb
in fruit and vegetable. The double-stranded DNA including aptamers were immobilized ...on the electrode via Au-S bond. Due to the specific binding of aptamer and metal ions, the aptamers labelled with methylene blue or ferrocene were competed off the gold electrode, and the electrochemical signal was decreased. Under the optimal conditions, the electrochemical aptasensor showed linear response to Cd
and Pb
in the range of 0.1 to 1000 nmol/L, and the detection limits of Cd
and Pb
achieved 89.31 and 16.44 pmol/L (3σ), respectively. Excellent stability and reproducibility were exhibited with RSD 2.27% (Cd
) and 3.61% (Pb
). The digested fruit and vegetable were also tested, and the recoveries were in the range of 90.06% to 97.24%. Thus, this strategy held great potential in monitoring cadmium and lead pollution.
Due to the advantages of good structural tunability, easy processibility, and high mobility, donor-acceptor based polymers are proposed as promising thermoelectric (TE) materials. However, the ...trade-off phenomenon between Seebeck coefficient (S) and electrical conductivity (σ) severely impedes their TE performance. Although many efforts have been applied to decouple these two parameters, it remains to be a bottleneck. Recently, we found that two-dimensional (2D) BDTTT-based polymers displayed high S with moderate σ. Combining one-dimensional (1D) conjugated structure (DPP-EDOT) with 2D conjugated structure (BDTTT-DPP) by random copolymerization can endow the polymers with good S and σ, thus alleviating the conflict. Among the polymers, P(BDTTT-DPP)1:P(DPP-EDOT)2 (P12) displayed the best power factor of 12.30 μW m−1 K−2 at room temperature, which is 4 and 1.3 times higher than that of P(BDTTT-DPP) (P10) and P(DPP-EDOT) (P01), respectively. These results provide an attractive guidance for fabricating the TE polymers with high performance by random copolymerization of two-dimensional and one-dimensional monomers.
In order to alleviate the trade-off between Seebeck coefficient and electrical conductivity, a series of D-A-D′-A type copolymers were designed and synthesized via random copolymerization. Among them, P(BDTTT-DPP)1:P(DPP-EDOT)2 (P12) films displayed the highest power factor (12.30 μW m−1 K−2) at room temperature, which is 4 and 1.3 times higher than that of P(BDTTT-DPP) (P10) and P(DPP-EDOT) (P01), respectively. Display omitted
•The trade-off relationship between S and σ was successfully alleviated by random copolymerization.•The introduction of BDTTT-DPP units to DPP-EDOT chains endows the polymers with high S.•Introducing DPP-EDOT units to BDTTT-DPP backbones can improve σ.•The power factor of P12 is 4 and 1.3 times higher than that of P10 and P01, respectively.
Myocardial dysfunction is a common complication during sepsis and significantly contributes to the mortality of patients with septic shock. However, none of the available therapeutic strategies ...proven to be effective in patients with severe sepsis are designed specifically to target myocardial dysfunction. The purpose of the present study is to investigate the effect of rhynchophylline (Rhy) on LPS-induced myocardial dysfunction in mice. We found that pretreatment with Rhy significantly improved cardiac systolic dysfunction, increased stroke volume and cardiac output in mice challenged with LPS. LPS induced cardiac inhibitor-κBα (I-κBα) phosphorylation, tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) mRNA expression, and in turn increased cardiac TNF-α and IL-1β protein production, all of which were attenuated by pretreatment with Rhy. Immunohistochemistry revealed that TNF-α was found in infiltrated macrophages (F4/80+) and myocardium, and Rhy reduced TNF-α immunostaining in cardiac infiltrated macrophages in LPS-challenged mice. Furthermore, Rhy inhibited LPS-induced I-κBα phosphorylation and TNF-α production in cultured mouse peritoneal macrophages, but not in neonatal mouse cardiomyocytes. Pretreatment with Rhy significantly decreased the mortality of LPS-challenged mice. These results indicate that Rhy reduces cardiac dysfunction and improves survival via suppression of macrophage I-κBα phosphorylation in LPS-challenged mice, and suggest that Rhy may be a potential agent for the treatment of septic cardiac dysfunction.
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► Rhynchophylline inhibited LPS-induced I-κBα phosphorylation in macrophages. ► Rhynchophylline did not block LPS-induced TNF-α production in cardiomyocytes. ► Rhynchophylline inhibited LPS-induced cardiac I-κBα phosphorylation. ► Rhynchophylline inhibited LPS-induced cardiac TNF-α and IL-1β expression. ► Rhynchophylline improved cardiac dysfunction and survival in LPS-challenged mice.
Elderly patients are susceptible to postoperative infections with increased mortality. Analyzing with a deep learning model, the perioperative factors that could predict and/or contribute to ...postoperative infections may improve the outcome in elderly. This was an observational cohort study with 2014 elderly patients who had elective surgery from 28 hospitals in China from April to June 2014. We aimed to develop and validate deep learning-based predictive models for postoperative infections in the elderly. 1510 patients were randomly assigned to be training dataset for establishing deep learning-based models, and 504 patients were used to validate the effectiveness of these models. The conventional model predicted postoperative infections was 0.728 (95% CI 0.688–0.768) with the sensitivity of 66.2% (95% CI 58.2–73.6) and specificity of 66.8% (95% CI 64.6–68.9). The deep learning model including risk factors relevant to baseline clinical characteristics predicted postoperative infections was 0.641 (95% CI 0.545–0.737), and sensitivity and specificity were 34.2% (95% CI 19.6–51.4) and 88.8% (95% CI 85.6–91.6), respectively. Including risk factors relevant to baseline variables and surgery, the deep learning model predicted postoperative infections was 0.763 (95% CI 0.681–0.844) with the sensitivity of 63.2% (95% CI 46–78.2) and specificity of 80.5% (95% CI 76.6–84). Our feasibility study indicated that a deep learning model including risk factors for the prediction of postoperative infections can be achieved in elderly. Further study is needed to assess whether this model can be used to guide clinical practice to improve surgical outcomes in elderly.
Antioxidant peptides are widely used in many fields due to their biological activities such as anti-cancer, anti-induction and anti-aging. However, little information is available concerning the ...peptides production by enzymatic hydrolysis of casein from goat milk. In this study, response surface methodology (RSM) was applied to optimize the conditions of the hydrolysis of goat milk casein by proteases (alcalase in combination with papain) to increase the antioxidant activity of the peptides. The results showed that the optimal hydrolysis conditions were as follows: temperature of 61°C, enzyme/substrate ratio (E/S) of 5.6%, and protease ratio (papain: alcalase) of 1.8:1. Under the optimal conditions, the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity significantly increased (1.17 folds compared to un-optimized conditions). Furthermore, Fe2+ chelating ability and superoxide radical scavenging activity increased 1.02 folds and 1.14 folds, respectively. The antioxidant activity was significantly improved after optimization and provided a basis for the study of the antioxidant effects of hydrolysed goat milk casein.
Quantitatively predicting the reactivity of dynamic covalent reaction is essential to understand and rationally design complex structures and reaction networks. In this work, we quantified the ...reactivity of aldehydes and amines in various rapid imine formation in aqueous solution by microfluidic NMR. Investigation of reaction kinetics allows us to quantify the forward rate constants k + by an empirical equation, of which three independent parameters were introduced as reactivity parameters of aldehydes ( S E , E ) and amines ( N ). Furthermore, these reactivity parameters were successfully used to predict the unknown forward rate constants of imine formation. Finally, two competitive reaction networks were rationally designed based on the proposed reactivity parameters. Our work has demonstrated the capability of microfluidic NMR in quantifying the kinetics of label-free chemical reactions, especially rapid reactions that complete in minutes.
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