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Despite advances in understanding the factors that cause many neurodegenerative diseases (NDs), no current therapies have yielded significant results. Cerium oxide nanoparticles (CeONPs) have recently emerged as therapeutics for the treatment of NDs due to their antioxidant properties. This report summarizes the recent findings regarding CeONPs in treatment of various NDs, including Alzheimer's disease, Parkinson's disease, multiple sclerosis, ischemic stroke and amyotrophic lateral sclerosis. Interest in CeONPs as a potential nanomedicine for NDs has increased due to: their ability to alter signaling pathways, small diameter allowing passage through the blood-brain barrier and scavenging of reactive oxygen species. Due to these properties, CeONPs could eventually revolutionize existing treatments for NDs.

In this paper, we introduce a new approach for altering the properties of bridged polysilsesquioxane xerogels using post-processing moaljzation of the polymeric network. The bridging organic group contains latent fbnctionalities that can be liberated thermally, photochemically, or by chemical means after the gel has been processed to a xerogel. These modifications can produce changes in density, volubility, porosity,' and or chemical properties of the material. Since every monomer possesses two latent functional groups, the technique allows for the introduction of high levels of functionality in hybrid organic-inorganic materials. Dialkylenecarbonate-bridged polysilsesquioxane gels were prepared by the sol-gel polymerization of bis(triethoxysilylpropyl)carbonate(1) and bis(triethoxysilylisobutyl)-carbonate (2). Thermal treatment of the resulting non-porous xerogels and aerogels at 300-350 'C resulted in quantitative decarboxylation of the dialkylenecarbonate bridging groups to give new hydroxyalkyl and olefinic substituted polysilsesquioxane monolithic xerogels and aerogels that can not be directly prepared through direct sol-gel polymerization of organotrialkoxysilanes.

Effects of molecular weight of methylphenyl‐containing vinylsiloxy‐functionalized terpolysiloxanes on their UV‐activated crosslinking by hydrosilylation at room temperature in air, shelf life stability of “all‐in‐one” pastes prepared from them for additive manufacturing, and mechanical properties of the resulting crosslinked elastomers, are investigated. It is found that while rheology of pastes containing base polymers, trimethylsilylated silica fillers, and thixotropic additives is not significantly affected by the base polymer molecular weight but is dominated by the filler concentration, the pastes based on higher molecular weight polymers exhibit faster crosslinking (corresponding to higher catalyst turnover numbers) and their crosslinked elastomers show transient strain‐induced crystallization. The latter appears in networks from terpolymers with degrees of polymerization (DP) of 240 and above (corresponding to about one half of the critical polydimethylsiloxane chain length for entanglement formation of DP = 460), within the temperature range of −80 to −30 °C, characteristic for polydimethylsiloxane melting transition. It is believed that this is the first time an observation of this chain length effect is reported for polysiloxane elastomers and that the properties reported herein can be expected to have major implications on the application potential of these polymers in both additive manufacturing and performance of their elastomers at sub‐ambient temperatures.

In search of "inks" for additive manufacturing of silicone rubber parts, three different types of "all-in-one" pastes with suitable rheological flow properties, ultraviolet (UV)-activated fast cross-linking by hydrosilylation in air at room temperature (as quick as 20−30 s), and shelf lives of over six months in the dark and 6−9 days in laboratory daylight, depending on paste composition, have been developed. The pastes are based on vinylsiloxy-functionalized, completely amorphous, linear terpolysiloxanes containing predominantly dimethylsiloxy-, DiMeS, repeat units with small amounts (typically less than 5 mol %), of diphenylsiloxy-, DiPhS, methylphenylsiloxy-, MePhS, or diethylsiloxy-, DiEtS, crystallization disruptors. The base polymers were compounded with trimethylsilylated hydrophobic silica fillers, thixotropic flow agents, hydrosilyl-functionalized oligomeric crosslinkers, and catalytic systems containing either platinum(II) acetylacetonate, Pt(AcAc) 2 , or trimethyl(methylcyclopentadienyl)platinum(IV), MeCpPtMe 3 , and diethyl azodicarboxylate, DEAD, catalyst inhibitors. Paste preparation, steady and oscillatory shear rheology, and UV-activated cross-linking and shelf-life stabilities are described.