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Background: Ureaplasma spp. can be classified into different serovars. It is unknown whether distinct serovars are associated with clinical signs and symptoms. Methods: We conducted a multicentre cross-sectional study. U. parvum serovars were identified on the basis of their multiple-banded antigen (MBA) genes. After adjusting for demographic variables and other reproductive tract infections, the odds ratio (OR) and 95% confidence interval (CI) were calculated to determine the impact of U. parvum serovars on clinical symptoms. Results: Among 5,277 individuals, U. parvum serovars 3 and 6 were the most prevalent serovars (17.9% and 16.0%, respectively). Potential confounders, such as age, body mass index (BMI), ethnicity, education level, contraceptive methods, number of sexual partners, gravidity, parity, and other sexually transmitted infections (STIs) that are associated with clinical symptoms (P < 0.1) were adjusted for in the univariate analysis. U. parvum serovar 14 was strongly positively associated with certain clinical symptoms, including redness and swelling of the vaginal wall (crude OR: 3.53, 95% CI: 1.92–6.49; adjusted OR: 5.21, 95% CI: 2.56–10.58), cervical bleeding and swelling (crude OR: 3.89, 95% CI: 2.38–6.36; adjusted OR: 7.37, 95% CI: 3.82–14.23), and cervical ectropion (crude OR: 2.08, 95% CI: 1.25–3.45; adjusted OR: 3.04, 95% CI: 1.60–5.74). In contrast, U. parvum serovar 3 was negatively associated with a variety of clinical symptoms, whereas no correlations were detected between U. parvum serovars 1and 6 with clinical symptoms. Conclusions: Different U. parvum serovars exhibit distinct correlations with clinical symptoms, suggesting that U. parvum serovars are pathogenically heterogeneous and that further differentiation of serovars may be necessary. Trial registration: The study was registered with ClinicalTrials.gov (https://www.clinicaltrials.gov; ID: NCT04694495; Registration Date: 2021–01-05). [ABSTRACT FROM AUTHOR]

The DP780 material was subjected to constant temperature tensile test in the temperature range of 20-140 and the strain rate range of 0.001-0.1s-1, and the true stress and strain change trends were analyzed. The constitutive equations of materials were established based on the Norton-Hoff model, which might better reflect the shaping constitutive relationship of DP780 during different cold forming processes. Combined with the Norton-Hoff constitutive model and friction model related to temperature and pressure,the combination of theoretical research and numerical simulation was used to study the mechanism and macroscopic characteristics of deformation heating and friction heating of DP780 steel plates. According to the theory of complete thermal coupling numerical simulation, considering the coupling analysis of temperature field, stress field and strain field, a research method of stamping was proposed considering deformation heat and friction heat effects. Through the stamping experiments, the forming results and springback characterization of DP780 steel plates applied to U-shaped parts were obtained. Comparing the simulation results of the traditional cold stamping and the new analytical method considering self-heating effects, it is found that the new stamping forming research method improves the accuracy by 10.1% on the sidewall and the accuracy by 23.2% at the flange. [ABSTRACT FROM AUTHOR]

Metal-free carbon-based materials are one of the most promising electrocatalysts toward 2-electron oxygen reduction reaction (2e-ORR) for on-site production of hydrogen peroxide (H 2 O 2 ), which however suffer from uncontrollable carbonizations and inferior 2e-ORR selectivity. To this end, a polydopamine (PDA)-modified carbon catalyst with a dipole-dipole enhancement is developed via a calcination-free method. The H 2 O 2 yield rate outstandingly reaches 1.8 mol g cat -1 h -1 with high faradaic efficiency of above 95% under a wide potential range of 0.4-0.7 V RHE , overwhelming most of carbon electrocatalysts. Meanwhile, within a lab-made flow cell, the synthesized ORR electrode features an exceptional stability for over 250 h, achieved a pure H 2 O 2 production efficacy of 306 g kWh -1 . By virtue of its industrial-level capabilities, the established flow cell manages to perform a rapid pulp bleaching within 30 min. The superior performance and enhanced selectivity of 2e-ORR is experimentally revealed and attributed to the electronic reconfiguration on defective carbon sites induced by non-covalent dipole-dipole influence between PDA and carbon, thereby prohibiting the cleavage of O-O in OOH intermediates. This proposed strategy of dipole-dipole effects is universally applicable over 1D carbon nanotubes and 2D graphene, providing a practical route to design 2e-ORR catalysts., (© 2023 Wiley‐VCH GmbH.)