Wavelength-Gated Adaptation of Hydrogel Properties via Photo-Dynamic Multivalency in Associative Star Polymers.

Responsive materials, such as switchable hydrogels, have been largely engineered for maximum changes between two states. In contrast, adaptive systems target distinct functional plateaus between these maxima. Here, we demonstrate how the photostationary state (PSS) of an E/Z-arylazopyrazole photoswitch can be tuned by the incident wavelength across a wide color spectrum, and how this behavior can be exploited to engineer the photo-dynamic mechanical properties of hydrogels based on multivalent photoswitchable interactions. We show that these hydrogels adapt to the wavelength-dependent PSS and the number of arylazopyrazole units by programmable relationships. Hence, our material design enables the facile adjustment of the mechanical properties without laborious synthetic efforts. The concept goes beyond the classical switching from state A to B, and demonstrates pathways for a truly wavelength-gated adaptation of hydrogel properties potentially useful to engineer cell fate or in soft robotics.

pH Tuning of Water-Soluble Arylazopyrazole Photoswitches.

Arylazopyrazoles are an emerging class of photoswitches with redshifted switching wavelength, high photostationary states, long thermal half-lives and facile synthetic access. Understanding pathways for a simple modulation of the thermal half-lives, while keeping other parameters of interest constant, is an important aspect for out-of-equilibrium systems design and applications. Here, it is demonstrated that the thermal half-life of a water-soluble PEG-tethered arylazo-bis(o-methylated)pyrazole (AAP) can be tuned by more than five orders of magnitude using simple pH adjustment, which is beyond the tunability of azobenzenes. The mechanism of thermal relaxation is investigated by thorough spectroscopic analyses and density functional theory (DFT) calculations. Finally, the concepts of a tunable half-life are transferred from the molecular scale to the material scale. Based on the photochromic characteristics of E- and Z-AAP, transient information storage is showcased in form of light-written patterns inside films cast from different pH, which in turn leads to different times of storage. With respect to prospective precisely tunable materials and time-programmed out-of-equilibrium systems, an externally tunable half-life is likely advantageous over changing the entire system by the replacement of the photoswitch.

Enhancing the Safe and Effective Management of Chronic Pain in Accountable Care Organization Primary Care Practices in Kentucky.

Chronic pain is a prevalent chronic condition with significant burden and economic impact in the United States. Chronic pain is particularly abundant in primary care, with an estimated 52% of chronic pain patients obtaining care from primary care physicians (PCPs). However, PCPs often lack adequate training and have limited time and resources to effectively manage chronic pain. Chronic pain management is complex in nature because of high co-occurrence of psychiatric disorders and other medical comorbidities in patients. This article describes a quality improvement initiative conducted by the American College of Physicians (ACP), in collaboration with the Kentucky ACP Chapter, and the Center for Health Services and Outcomes Research at the Johns Hopkins Bloomberg School of Public Health, to enhance chronic pain management in 8 primary care practices participating in Accountable Care Organizations in Kentucky, with a goal of enhancing the screening, diagnosis, and treatment of patients with chronic pain.