The literature on the effect of age on saliva production, which has implications for health, quality of life, differential diagnosis, and case management, remains inconclusive. Physiological changes, motor and sensory, are frequently reported with increasing age. It was hypothesized that there would be a change in saliva production with older age. Whole stimulated saliva was collected by asking participants to chew gauze for 1 minute and then comparing the weight of saliva produced according to age and sex. Data were collected in activity centers for older adults, workplaces, universities, and participants' homes. Five hundred forty healthy individuals (aged 20-97) in three age groups (young = 20-30; middle-aged = 40-50; older ≥ 70) participated (90 men and 90 women in each group). A decrement in saliva production was identified for age in that the young and older participants and the middle-aged and older participants differed significantly from each other, but no difference was found between the young and middle-aged participants. The main effect of sex was not significant, nor was the interaction of age and sex. The results have implications for research and clinical work, including the differential diagnosis and subsequent management of salivary flow impairment due to age or underlying medical diagnosis or treatment. The assessment tool is easily administered and inexpensive and lends itself to use in many different clinical and research settings by different professionals.

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Artificial solid electrolyte interphases have provided a path to improved cycle life for high energy density, next-generation anodes like lithium metal. Although long cycle life is necessary for widespread implementation, understanding and mitigating the effects of aging and self-discharge are also required. Here, we investigate several coating materials and their role in calendar life aging of lithium. We find that the oxide coatings are electronically passivating whereas the LiF coating slows charge transfer kinetics. Furthermore, the Coulombic loss during self-discharge measurements improves with the oxide layers and worsens with the LiF layer. It is found that none of the coatings create a continuous conformal, electronically passivating layer on top of the deposited lithium nor are they likely to distribute evenly through a porous deposit, suggesting that none of the materials are acting as an artificial solid electrolyte interphase. Instead, they likely alter performance through modulating lithium nucleation and growth.

Primarily driven by structural biology, the rapid advances in cryogenic electron microscopy (cryo-EM) techniques are now being adopted and applied by materials scientists. Samples that inherently have electron transparency can be rapidly frozen (vitrified) in amorphous ice and imaged directly on a cryogenic transmission electron microscopy (cryo-TEM), however this is not the case for many important materials systems, which can consist of layered structures, embedded architectures, or be contained within a device. Cryogenic focused ion beam (cryo-FIB) lift-out procedures have recently been developed to extract intact regions and interfaces of interest, that can then be thinned to electron transparency and transferred to the cryo-TEM for characterization. Several detailed studies have been reported demonstrating the cryo-FIB lift-out procedure, however due to its relative infancy in materials science improvements are still required to ensure the technique becomes more accessible and routinely successful. Here, we review recent results on the preparation of cryo-TEM lamellae using cryo-FIB and show that the technique is broadly applicable to a range of soft matter and beam sensitive energy materials. We then present a tutorial that can guide the materials scientist through the cryo-FIB lift-out process, highlighting recent methodological advances that address the most common failure points of the technique, such as needle attachment, lift-out and transfer, and final thinning.