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Abstract Background Gram-negative bacteria (GNB) are becoming increasingly resistant to a wide variety of antibiotics. There are currently limited treatments for GNB, and the combination of antibiotics with complementary mechanisms has been reported to be a feasible strategy for treating GNB infection. The inability to cross the GNB outer membrane (OM) is an important reason that a broad spectrum of Gram-positive only class of antibiotics (GPOAs) is lacking. Polymyxins may help GPOAs to permeate by disrupting OM of GNB. Objective To identify what kind of GPOAs can be aided to broaden their anti-GNB spectrum by polymyxins, we systematically investigated the synergy of eight GPOAs in combination with colistin (COL) and polymyxin B (PMB) against GNB in vitro. Methods The synergistic effect of COL or PMB and GPOAs combinations against GNB reference strains and clinical isolates were determined by checkerboard tests. The killing kinetics of the combinations were assessed using time-kill assays. Results In the checkerboard tests, polymyxins-GPOAs combinations exert synergistic effects characterized by species and strain specificity. The synergistic interactions on P. aeruginosa strains are significantly lower than those on strains of A. baumannii, K. pneumoniae and E. coli. Among all the combinations, COL has shown the best synergistic effect in combination with dalbavancin (DAL) or oritavancin (ORI) versus almost all of the strains tested, with FICIs from 0.16 to 0.50 and 0.13 to

Abstract Garnet oxide is one of the most promising solid electrolytes for solid-state lithium metal batteries. However, the traditional interface modification layers cannot completely block electron migrating from the current collector to the interior of the solid-state electrolyte, which promotes the penetration of lithium dendrites. In this work, a highly electron-blocking interlayer composed of potassium fluoride (KF) is deposited on garnet oxide Li6.4La3Zr1.4Ta0.6O12 (LLZTO). After reacting with melted lithium metal, KF in-situ transforms to KF/LiF interlayer, which can block the electron leakage and inhibit lithium dendrite growth. The Li symmetric cells using the interlayer show a long cycle life of ~3000 hours at 0.2 mA cm−2 and over 350 hours at 0.5 mA cm−2 respectively. Moreover, an ionic liquid of LiTFSI in C4mim-TFSI is screened to wet the LLZTO|LiNi0.8Co0.1Mn0.1O2 (NCM) positive electrode interfaces. The Li|KF-LLZTO | NCM cells present a specific capacity of 109.3 mAh g−1, long lifespan of 3500 cycles and capacity retention of 72.5% at 25 °C and 2 C (380 mA g−1) with an average coulombic efficiency of 99.99%. This work provides a simple and integrated strategy on high-performance quasi-solid-state lithium metal batteries.

This study selected relevant data of China from 2006 to 2019 and adopted a panel vector autoregression (PVAR) model to conduct an empirical analysis on the dynamic mechanism of a series of problems including “FDI (foreign direct investment), economic scale, and environmental pollution,” “FDI, industrial structure, and environmental pollution,” and “FDI, production technology, and environmental pollution.” Our research results showed that there are differences in the optimal lag order under different conditions, such as under the action mechanism of economic scale and industrial structure, and the optimal lag order was 1, while under the action mechanism of production technology, its value was 2. FDI had a long-term effect on the environment; under the dual-action mechanism of economic scale and industrial structure, the environmental effect of FDI reached the maximum within 2 periods, the effect lasted a relatively long time, and the response of environmental pollution to the technological level reached the maximum between the fourth period and the sixth period. In terms of the overall situation in China, the FDI did not produce an obvious effect on environmental pollution; on the contrary, it exhibited a trend of environmental improvement, which varied with the action mechanism and the region; and also, the improvement of technological level can also significantly improve the quality of environment.