Search

Molecular strain can be introduced to influence the outcome of chemical reactions. Once a thermodynamic product is formed, however, reversing the course of a strain-promoted reaction is challenging. Here, a reversible, strain-promoted polymerization in cyclic DNA is reported. The use of nonhybridizing, single-stranded spacers as short as a single nucleotide in length can promote DNA cyclization. Molecular strain is generated by duplexing the spacers, leading to ring opening and subsequent polymerization. Then, removal of the strain-generating duplexers triggers depolymerization and cyclic dimer recovery via enthalpy-driven cyclization and entropy-mediated ring contraction. This reversibility is retained even when a protein is conjugated to the DNA strands, and the architecture of the protein assemblies can be modulated between bivalent and polyvalent states. This work underscores the utility of using DNA not only as a programmable ligand for assembly but also as a route to access restorable bonds, thus providing a molecular basis for DNA-based materials with shape-memory, self-healing, and stimuli-responsive properties. [ABSTRACT FROM AUTHOR]

Background and Objectives The increasing number of people with dementia requires transparency and quality dementia education, training, and care. This scoping review aimed to determine the key elements of national or state-wide standards on dementia education and training that could underpin the development of international standards for dementia workforce training and education. Research Design and Methods The English-language peer-reviewed and gray literature were searched (2010–20). Key search domains were training, workforce, standards/frameworks, and dementia. Results Thirteen standards were identified from the United Kingdom (n = 5), the United States (n = 4), Australia (n = 3), and Ireland (n = 1). Most standards focused on training health care professionals with some including people in customer-centric settings, people living with dementia, and informal carers or the general community. Seventeen training topics were identified in 10 or more of the 13 standards. Cultural safety, rural issues, health care professional self-care, digital literacy, and health promotion topics were less commonly reported. The barriers to standards implementation were lack of organizational support, lack of access to relevant training, low staff literacy, lack of funding, high staff turnover, ineffective past program cycles, and inconsistent service delivery. Enablers included a strong implementation plan, funding, strength of partnerships, and building on previous work. Discussion and Implications The U.K. Dementia Skills and Core Training Standard, the Irish Department of Health Dementia Together, and the National Health Services Scotland Standard are the recommended strongest standards for underpinning the development of international standards. It is essential that training standards are tailored to the needs of the consumer, worker, and regions. [ABSTRACT FROM AUTHOR]