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Lithium bis͑fluorosulfonyl͒imide ͑LiFSI͒ has been investigated as a conducting salt of liquid electrolytes for lithium-ion batteries. It shows high solubility in most polar solvents, and a concentration of 5 M ͑mol dm −3 ͒ is reached in dimethyl carbonate ͑DMC͒ despite its low dielectric constant. LiFSI shows a thermal stability up to 180°C on the thermogravimetric test. Compared with the LiPF 6 /carbonate electrolytes, the LiFSI-based ones show higher ionic conductivities over a wide temperature range ͑−50 to 50°C͒ and higher lithium-ion transference numbers ͑t Li +͒ of 0.5-0.6. The conductivities of the LiFSI/DMC electrolyte over the 0.1-5 M concentration range obey a modified Casteel-Amis equation. The temperature dependence of 1 M LiFSI/DMC/EMC ͑3:7, v/v͒ is governed by the Vogel-Tammann-Fulcher relationship. The Fourier transform infrared spectra of the LiFSI/DMC electrolytes at different concentrations are systematically investigated. DMC shows significant spectral variations upon adding LiFSI, indicating strong interaction of Li + cations with the solvent molecules. We also found that the compatibility with graphite anode and LiFePO 4 cathode in the LiFSI-based electrolyte is as good as that in the LiPF 6 -based one, though aluminum ͑Al͒ corrosion occurs above 4 V vs Li + /Li. LiFSI is a very good contender to replace the latter, with increased performances and safety.

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Helminth infections and nutrition can independently alter the composition and abundance of the gastrointestinal microbiota, however, their combined effect is poorly understood. Here, we used the T. retortaeformis-rabbit system to examine how the helminth infection and host restriction from coprophagy/ready-to-absorb nutrients affected the duodenal microbiota, and how these changes related to the acquired immune response at the site of infection. A factorial experiment was performed where the bacterial community, its functionality and the immune response were examined in four treatments (Infect, Infect+Collar, Control+Collar and Control). Helminths reduced the diversity and abundance of the microbiota while the combination of parasites and coprophagic restriction led to a more diversified and abundant microbiota than infected cases, without significantly affecting the intensity of infection. Animals restricted from coprophagy and free from parasites exhibited the richest and most abundant bacterial community. By forcing the individuals to absorb nutrients from less digested food, the coprophagic restriction appears to have facilitated the diversity and proliferation of bacteria in the duodenum. Changes in the microbiota were more clearly associated with changes in the immune response for the infected than the nutrient restricted animals. The functional and metabolic characteristics of the duodenal microbiota were not significantly different between treatments. Overall, infection and diet affect the gut microbiota but their interactions and outcome can be complex. These findings can have important implications for the development of control measures to helminth infections where poor nutrition/malnutrition can also be a concern.

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