Dynamics of magnetization at infinite temperature in a Heisenberg spin chain

Understanding universal aspects of quantum dynamics is an unresolved problem in statistical mechanics. In particular, the spin dynamics of the one-dimensional Heisenberg model were conjectured as to belong to the Kardar-Parisi-Zhang (KPZ) universality class based on the scaling of the infinite-temperature spin-spin correlation function. In a chain of 46 superconducting qubits, we studied the probability distribution of the magnetization transferred across the chain's center, [Formula: see text]. The first two moments of [Formula: see text] show superdiffusive behavior, a hallmark of KPZ universality. However, the third and fourth moments ruled out the KPZ conjecture and allow for evaluating other theories. Our results highlight the importance of studying higher moments in determining dynamic universality classes and provide insights into universal behavior in quantum systems.

A qualitative process evaluation of a diabetes navigation program embedded in an endocrine specialty center in rural Appalachian Ohio

BACKGROUND

Diabetes in the United States has reached epidemic proportions and the people of Appalachia have been disproportionately affected by this disease. Strategies that complement standard diabetes care are critically important to mitigate the risk of complications, reduce health expenditures, and improve the quality of life of patients living in rural Appalachia. The purpose of this study was to conduct a qualitative process evaluation of a patient navigation program for diabetes after its first year of implementation.

METHODS

The process evaluation assessed how the Diabetes Navigation Program was delivered as well as how it was experienced by the navigators, providers, health administrators, and office staff at an endocrine specialty center in rural Appalachian Ohio. We employed total population sampling to conduct in-depth, face-to-face interviews with all providers, health administrators, staff, and navigators at a Diabetes Endocrine Center. Interviews were transcribed, coded, and analyzed via content and thematic analyses using NVivo 11 software.

RESULTS

Seventeen individuals (providers n = 5, health administrators n = 4, office staff members n = 3, and navigators n = 5) participated in in-depth, face-to-face interviews (age = 44.7 ± 11.6 years, 82.4% female, 94.1% white, 13.3 ± 9.6 years work experience). Fidelity of implementation: The navigation team carried out most of the activities denoted in the Work Plan, therefore the program was implemented somewhat successfully. Qualitative analysis revealed three themes: 1) The navigator addresses sources of health disparities: All participants described the role of the diabetes navigator as someone who is knowledgeable about diabetes and able to identify and address health disparities. 2) The navigators are the eyes in the community and the patients' homes: Navigators offered providers and clinic staff a rare glimpse into the personal lives of patients, which led to the identification of unrecognized barriers. 3) Difficulties with cross-system integration of services: Differences in the organizational culture and vision of the specialty center and navigation office contributed to systemic barriers.

CONCLUSIONS

Overall, this process evaluation highlights the importance of coordinating providers, health administrators, medical office staff, and navigators to address barriers to diabetes care. Forthcoming research is needed to document the clinical effectiveness and sustainability of the Diabetes Navigation Program in rural Appalachia.

Activity participation and affect among nursing home residents: support for a behavioural model of depression

One focus of interventions being developed for depression in nursing homes is increasing pleasant events. The conceptual foundation of such interventions requires establishing links among activity levels, depressive symptoms and positive affect. We observed activity and affect among 28 nursing home residents, five-days-a-week for four weeks, and concurrently collected self-reported affect and depression data. Inclusion of intra-individual analyses using random effects models demonstrated considerable individual variability in the relationship between positive affect and activity, although the results broadly supported the association. Participants differed with regard to what types of events were pleasurable and with regard to the relationships among pleasure, interest and activity. Depression levels were related to some of these individual differences. Activity was related primarily to interest rather than pleasure and higher interest was related to fewer depressive symptoms. Our findings emphasize the importance of individually tailoring pleasant events interventions and suggest that prescriptive group activities are unlikely to prove effective as means for improving positive affect.