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A non-isocyanate synthetic route was used to generate 20 different ionic liquids containing either a carbamate or thiocarbamate functional group. 

Abstract The brain is organized into intrinsically connected functional networks that can be reliably identified during resting-state functional magnetic resonance imaging (fMRI). Healthy aging is marked by decreased network segregation, which is linked to worse cognitive functioning, but aging-related changes in emotion are less well characterized. Valence bias, which represents the tendency to interpret emotionally ambiguous information as positive or negative, is more positive in older than younger adults and is associated with differences in task-based fMRI activation in the amygdala, prefrontal cortex, and a cingulo-opercular (CO) network. Here, we examined valence bias, age, and resting-state network segregation of 12 brain networks in a sample of 221 healthy individuals from 6 to 80 years old. Resting-state network segregation decreased linearly with increasing age, extending prior reports of de-differentiation across the lifespan. Critically, a more positive valence bias was related to lower segregation of the default mode network (DMN), due to stronger functional connectivity of the DMN with CO and, to a lesser extent, the ventral attention network (VAN) in all participants. In contrast to this overall segregation effect, in participants over 39 years old (who tend to show a positive valence bias), bias was also related to weaker connectivity between the DMN and Reward networks. The present findings indicate that specific interactions between the DMN, a task control network (CO), an emotion processing network (Reward), and, to a weaker extent, an attention network (VAN), support a more positive valence bias, perhaps through regulatory control of self-referential processing and reduced emotional reactivity in aging. The current work offers further insight into the functional brain network alterations that may contribute to affective well-being and dysfunction across the lifespan. 

Abstract The synthesis and characterization of a series of polyurethane ionenes using a non‐isocyanate approach is disclosed. Imidazole‐capped, urethane‐containing prepolymers are prepared by first reacting carbonyl diimidazole (CDI) with several poly(propylene glycol) (PPG) diols with variable molecular weight, followed by subsequent reaction with 3‐aminopropylimidazole (API). Polymerization with 1,4‐dibromomethylbenzene followed by anion exchange resulted in the desired polyurethane ionenes bearing the [NTf₂] counteranion as a series of viscous liquids. NMR and FTIR spectroscopy are used to characterize the intermediates and final ionenes, including molecular weight determination by end‐group analysis. A single glass transition temperature (T_g), as determined by differential scanning calorimetry (DSC), is observed for each ionene (−38 to −64 °C) with theT_gdecreasing with increasing PPG molecular weight. Thermogravimetric analysis (TGA) indicated a two‐step decomposition for each ionene, with the first being degradation of the PPG segment, followed by the urethane/ionic segment. Microphase separation is observed from x‐ray scattering profiles with Bragg distances that increased with increasing PPG molecular weight. Ionic conductivity is found to be inversely dependent upon DSCT_gat lower temperatures (RT and below); however, at higher temperatures, conductivity appears to be more dependent upon the ability of ionic aggregates caused by phase separation to interact.