Matrix Li-Yau-Hamilton estimates under Ricci flow and parabolic frequency.

We prove matrix Li-Yau-Hamilton estimates for positive solutions to the heat equation and the backward conjugate heat equation, both coupled with the Ricci flow. We then apply these estimates to establish the monotonicity of parabolic frequencies up to correction factors. As applications, we obtain some unique continuation results under the nonnegativity of sectional or complex sectional curvature.

Requisite role of dorsal raphé in contextual cocaine-memory reconsolidation.

Memory reconsolidation is a process by which labile drug memories are restabilized in long-term memory stores, permitting their enduring control over drug-seeking behaviors. In the present study, we investigated the involvement of the dorsal raphé nuclei (DRN) in cocaine-memory reconsolidation. Sprague-Dawley rats (male, female) were trained to self-administer cocaine in a distinct environmental context to establish contextual drug memories. They then received extinction training in a different context. Next, the rats were re-exposed to the cocaine-predictive context for 15 min to reactivate their cocaine memories or remained in their home cages (no-reactivation control). Memory reactivation was sufficient to increase c-Fos expression, an index of neuronal activation, in the DRN, but not in the median raphé nuclei, during reconsolidation, compared to no reactivation. To determine whether DRN neuronal activity was necessary for cocaine-memory reconsolidation, rats received intra-DRN baclofen plus muscimol (BM; GABAB/A agonists) or vehicle microinfusions immediately after or 6 h after a memory reactivation session conducted with or without lever access. The effects of DRN functional inactivation on long-term memory strength, as indicated by the magnitude of context-induced cocaine seeking, were assessed 72 h later. Intra-DRN BM treatment immediately after memory reactivation with or without lever access attenuated subsequent context-induced cocaine-seeking behavior, independent of sex. Conversely, BM treatment in the adjacent periaqueductal gray (PAG) immediately after memory reactivation, or BM treatment in the DRN 6 h after memory reactivation, did not alter responding. Together, these findings indicate that the DRN plays a requisite role in maintaining cocaine-memory strength during reconsolidation.

[Effects of cognition-related lifestyles on early cognitive decline in community older adults in China].

Objective: To investigate the distribution characteristics of cognition-related lifestyles of elderly in communities and explore the integrated effects on early cognitive decline. Methods: The participants were from the Project of Prevention and Intervention of Neurodegenerative Disease for Elderly in China. A total of 2 537 older adults aged ≥60 years without dementia in the 2015 baseline survey and the 2017 follow-up survey were included. The information about their cognition-related lifestyles, including physical exercise, social interaction, leisure activity, sleep quality, smoking status, and alcohol consumption, were collected through questionnaire survey and the integrated scores were calculated. Multivariate logistic regression analysis was used to assess the association between integrated cognition-related lifestyle score and early cognitive decline. Results: In the 2 537 older adults surveyed, 28.7% had score of 5-6, while only 4.8% had high scores for all 6 healthy lifestyles. Significant differences in healthy lifestyle factor distributions were observed between men and women. Multivariate logistic regression model showed that the risks for early cognitive decline in the older adults who had lifestyle score of 4 and 5-6 were lower than that in those with lifestyle score of 0-3 (OR=0.683, 95%CI: 0.457-1.019; OR=0.623, 95%CI: 0.398-0.976; trend P=0.030). In the women, the risks for early cognitive decline was lower in groups with score of 4 and 5-6 than in group with score of 0-3 (OR=0.491, 95%CI: 0.297-0.812; OR=0.556, 95%CI: 0.332-0.929; trend P=0.024). Conclusion: Cognition-related healthy lifestyles are associated with significantly lower risk for early cognitive decline in the elderly, especially in women.

Component-based allergen-microarray: der p 2 and Der f 2 dust mite sensitization is more common in patients with severe asthma

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