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Abstract: Thermal decomposition of anhydrous and moisture exposed LiPF6 solids were studied using thermogravimetry (TG). The effects of experimental conditions such as sample mass and inert gas atmosphere on decomposition kinetics were investigated. It was found that an experimental sample mass range of 5–10mg provided a reasonably constant activation energy value of approximately 116.0kJmol−1 for the decomposition of anhydrous LiPF6. The use of larger sample masses for the thermal decomposition study on TG resulted in lower activation energies and pre-exponential factors compared to smaller sample masses. This anomaly can be ascribed to inefficiencies in heat and mass transfer processes. Moisture exposed LiPF6 has an apparent activation energy value (123.7kJmol−1) that is higher than that of the anhydrous salt and this is thought to be associated with the partial formation of a LiPF6·HF adduct on the solid surface resulting from the absence of an efficient sweeping gas to remove decomposition by-products. The spontaneous decomposition rate constant of anhydrous LiPF6 at 298.15K has been determined to be 4.2×10−5 s−1. [Copyright &y& Elsevier]

The neuronal ubiquitin/proteasomal pathway has been implicated in the pathogenesis of Alzheimer's disease (AD). We now show that a component of the pathway, ubiquitin C-terminal hydrolase L1 (Uch-L1), is required for normal synaptic and cognitive function. Transduction of Uch-L1 protein fused to the transduction domain of HIV-transactivator protein (TAT) restores normal enzymatic activity and synaptic function both in hippocampal slices treated with oligomeric Abeta and in the APP/PS1 mouse model of AD. Moreover, intraperitoneal injections with the fusion protein improve the retention of contextual learning in APP/PS1 mice over time. The beneficial effect of the Uch-L1 fusion protein is associated with restoration of normal levels of the PKA-regulatory subunit IIalpha, PKA activity, and CREB phosphorylation.