A strontium ferrite modified separator for adsorption and catalytic conversion of polysulfides for excellent lithium-sulfur batteries.

Lithium-sulfur batteries (LSBs) have emerged as one of the ideal contenders for the upcoming generation of high energy storage devices due to their superb energy density. Nonetheless, the shuttle effect generated by intermediate lithium polysulfides (LiPSs) during cell cycling brings about capacity degradation and poor cycling stability of LSBs. Here, a versatile SrFe12O19 (FSO) and acetylene black (AB) modified PP separator is first presented to inhibit the shuttle effect. Thanks to the strong chemical interaction of Fe and Sr with polysulphides in FSO, it can trap LiPSs and provide catalytic sites for their conversion. Therefore, the cell using the FSO/AB@PP separator has a high initial discharge specific capacity (930 mA h g-1) at 2 C and lasts for 1000 cycles with a remarkably low fading rate (0.036% per cycle), while those using PE and AB@PP separators have inferior initial specific capacities (255 mA h g-1 and 652 mA h g-1, respectively) and fail within 600 cycles. This work proposes a novel approach for addressing the shuttle of LiPSs from a bimetallic oxide modified separator.

Characterization of the Microbiome and Host's Metabolites of the Lower Respiratory Tract During Acute Community-Acquired Pneumonia Identifies Potential Novel Markers.

Purpose: Community-acquired pneumonia (CAP) is one of the most frequently encountered infectious diseases worldwide. Few studies have explored the microbial composition of the lower respiratory tract (LRT) and host metabolites of CAP. We analyzed the microbial composition of the LRT and levels of host metabolites to explore new biomarkers for CAP. Patients and Methods: Bronchoalveolar lavage fluid (BALF) was collected from 28 CAP patients and 20 healthy individuals. Following centrifugation, BALF pellets were used for amplicon sequencing of a variable region of the bacterial 16S rDNA gene to characterize the microbial composition. Non-targeted metabolomics was used to detect host's metabolites in the supernatant. Results: Compared with healthy individuals, the bacterial alpha diversity in the LRT of CAP patients was significantly lower in CAP patients (p<0.05). On the bacterial genus level, over 20 genera were detected with lower relative abundance (p<0.05), while the relative abundance of Ruminiclostridium-6 was significantly higher in CAP patients. The levels of the host metabolites dimethyldisulfide, choline, pyrimidine, oleic acid and N-acetyl-neuraminic acid were all increased in BALF of CAP patients (p<0.05), while concentrations of lysophosphatidylcholines (LPC (12:0/0:0)) and phosphatidic acid (PA (20:4/2:0)) were decreased (p<0.05). Furthermore, the relative abundance of Parvimonas, Treponema-2, Moraxella, Aggregatibacter, Filifactor, Fusobacterium, Lautropia and Neisseria negatively correlated with concentrations of oleic acid (p<0.05). A negative correlation between the relative abundance of Treponema-2, Moraxella, Filifactor, Fusobacterium and dimethyldisulfide concentrations was also observed (p<0.05). In contrast, the relative abundance of Treponema-2, Moraxella, Filifactor, and Fusobacterium was found to be positively associated with concentrations of LPC (12:0/0:0) and PA (20:4/2:0) (p<0.05). Conclusion: The composition of the LRT microbiome differed between healthy individuals and CAP patients. We propose that some respiratory microbial components and host metabolites are potentially novel diagnostic markers of CAP.