Surveillance for adverse events following immunization with DTaP-containing combination vaccines in Linping, China, 2019-2022.

Background: The DTaP-Hib and DTaP-IPV/Hib combination vaccine can be used as a substitute for the diphtheria, tetanus, and acellular pertussis combined vaccine (DTaP). We aimed to evaluate the safety of multi-component vaccines containing DTaP by analyzing the reporting rates and characteristics of adverse events following immunization (AEFIs) in Linping District during the years 2019 to 2022. Methods: We obtained data of AEFI and vaccination from the National AEFI Surveillance System of China and Zhejiang Municipal Immunization Information Management System, respectively, during 2019-2022 for a descriptive, epidemiological analysis. Results: The total number of AEFI reported following vaccinations with DTaP-containing combination vaccines was 802 in Linping District from 2019 to 2022. The overall reporting rates of AEFIs following DTaP, DTaP-Hib, and DTaP-IPV/Hib vaccinations were 445.72 (537 cases), 536.29 (45 cases), and 306.13 (220 cases) per 100,000 doses in Linping District from 2019 to 2022, respectively. Only one case of a serious AEFI following DTaP vaccination, with a reporting rate of 0.83 per 100,000 doses. The composition ratio of vaccine product-related reactions for DTaP, DTaP-Hib, and DTaP-IPV/Hib were 99.81, 97.78, and 100.00%, respectively. The composition ratio of coincidental events for DTaP and DTaP-Hib were 0.19 and 2.22%, respectively. The reporting rates of total AEFIs for DTaP-IPV/Hib were lower than for DTaP. The reporting rate of local induration for DTaP-Hib was lower than for DTaP, and the reporting rates of local redness & swelling and local induration for DTaP-IPV/Hib were both lower than for DTaP. DTaP-IPV/Hib had a higher proportion of AEFIs in first quarter compared to DTaP. The reporting rate after the second dose of DTaP-Hib was higher than that of DTaP, and the reporting rates of AEFIs after the first dose and third dose of DTaP-IPV/Hib were lower than DTaP. Conclusion: The reported AEFIs to multi-component vaccines containing DTaP components during 2019-2022 in Linping District were mainly mild vaccine reactions. DTaP-containing combination vaccines demonstrated a good safety profile.

Giant magnetocaloric effect in spin supersolid candidate Na2BaCo(PO4)2.

Supersolid, an exotic quantum state of matter that consists of particles forming an incompressible solid structure while simultaneously showing superfluidity of zero viscosity1, is one of the long-standing pursuits in fundamental research2,3. Although the initial report of 4He supersolid turned out to be an artefact4, this intriguing quantum matter has inspired enthusiastic investigations into ultracold quantum gases5-8. Nevertheless, the realization of supersolidity in condensed matter remains elusive. Here we find evidence for a quantum magnetic analogue of supersolid-the spin supersolid-in the recently synthesized triangular-lattice antiferromagnet Na2BaCo(PO4)2 (ref. 9). Notably, a giant magnetocaloric effect related to the spin supersolidity is observed in the demagnetization cooling process, manifesting itself as two prominent valley-like regimes, with the lowest temperature attaining below 100 mK. Not only is there an experimentally determined series of critical fields but the demagnetization cooling profile also shows excellent agreement with the theoretical simulations with an easy-axis Heisenberg model. Neutron diffractions also successfully locate the proposed spin supersolid phases by revealing the coexistence of three-sublattice spin solid order and interlayer incommensurability indicative of the spin superfluidity. Thus, our results reveal a strong entropic effect of the spin supersolid phase in a frustrated quantum magnet and open up a viable and promising avenue for applications in sub-kelvin refrigeration, especially in the context of persistent concerns about helium shortages10,11.

Development of electrochemical high-speed atomic force microscopy for visualizing dynamic processes of battery electrode materials.

Development of lithium ion batteries with ultrafast charging rate as well as high energy/power densities and long cycle-life is one of the imperative works in the field of batteries. To achieve this goal, it requires not only to develop new electrode materials but also to develop nano-characterization techniques that are capable of investigating the dynamic evolution of the surface/interface morphology and property of fast charging electrode materials during battery operation. Although electrochemical atomic force microscopy (EC-AFM) holds high spatial resolution, its imaging speed is too slow to visualize dynamics occurring on the timescale of minutes. In this article, we present an electrochemical high-speed AFM (EC-HS-AFM), developed by addressing key technologies involving optical detection of small cantilever deflection, dual scanner capable of high-speed and wide-range imaging, and electrochemical cell with three electrodes. EC-HS-AFM imaging from 1 fpm to ∼1 fps with a maximum scan range of 40 × 40 µm2 has been stably and reliably realized. Dynamic morphological changes in the LiMn2O4 nanoparticles during cyclic voltammetry measurements in the 0.5 mol/l Li2SO4 solution were successfully visualized. This technique will provide the possibility of tracking dynamic processes of fast charging battery materials and other surface/interface processes such as the formation of the solid electrolyte interphase layer.

Visualization of Electrochemical Cycling-Induced Dimension Change in LiMn2O4 Nanoparticles by High-Speed Atomic Force Microscopy.

Exploring dynamic dimension change and lithium-ion diffusion kinetics of active nanoparticles is important to further improve the qualities of lithium-ion batteries (LIBs), such as the cycle life and charge rate. For advancing such research, an imaging technique that is capable of operating in an electrochemical environment with high spatial and temporal resolutions is really needed. In this work, we successfully developed electrochemical high-speed atomic force microscopy (EC-HS-AFM), which enabled nanoscale imaging at the rate of ∼1 frame/s during electrochemical cycling. The dimensional evolutions of LiMn2O4 single nanoparticles accompanying an insertion/extraction reaction of lithium ions were visualized. The surface area-potential hysteresis loops of the single nanoparticles at different sweep rates were quantitatively extracted from the successive HS-AFM images or video. The first-order derivative of the hysteresis loop was interestingly similar to the cyclic voltammetry (CV). Moreover, the EC-HS-AFM experiments confirmed that the utilization of the nanoparticles in the cathode can indeed improve the rate performance of the LIBs. These results demonstrated that EC-HS-AFM would be a promising tool to study dimensional evolutions and lithium-ion diffusion kinetics at a nanoscale.