Super-resolution of sodium images from simultaneous 1 H MRF/23 Na MRI acquisition.

In this work, we introduce a super-resolution method that generates a high-resolution (HR) sodium (23 Na) image from simultaneously acquired low-resolution (LR) 23 Na density-weighted MRI and HR proton density, T1 , and T2 maps from proton (1 H) MR fingerprinting in the brain at 7 T. The core of our method is a partial least squares regression between the HR (1 H) images and the LR (23 Na) image. An iterative loop and deconvolution with the point spread function of each acquired image were included in the algorithm to generate a final HR 23 Na image without losing features from the LR 23 Na image. The method was applied to simultaneously acquired HR proton and LR sodium data with in-plane resolution ratios between sodium and proton data of 3.8 and 1.9 and the same slice thickness. Four volunteers were scanned to evaluate the method's performance. For the data with a resolution ratio of 3.8, the mean absolute difference between the generated and ground truth HR 23 Na images was in the range of 1.5%-7.2% of the ground truth with a multiscale structural similarity index (M-SSIM) of 0.93 ± 0.03. For the data with a resolution ratio of 1.9, the mean absolute difference was in the range of 4.8%-6.3% with an M-SSIM of 0.95 ± 0.01.

Race moderates the association between adult attachment avoidance and the cortisol awakening response among young sexual minority men.

Adult attachment, or the ways in which individuals develop and maintain trusting and loving relationships with peers and romantic partners, has been demonstrated to influence hypothalamic-pituitary-adrenal (HPA) axis functioning among young sexual minority men (YSMM). Theory and preliminary evidence suggest that differences in the lived experiences of White and Black sexual minority young adults may influence the way in which adult attachment influences the HPA-axis functioning. We sought to further this field of inquiry by examining if race moderates the association between adult attachment insecurity (i.e., avoidance and anxiety) and HPA-axis functioning among YSMM. Sixty-three YSMM participated in a 5-day daily diary study in which they completed a baseline survey to assess adult attachment orientation and provided saliva samples 4 times per day over a 5-day period in order to measure cortisol across the day. Three-level hierarchical linear modeling was used to examine the association between adult attachment, the cortisol awakening response (CAR), diurnal cortisol, and the moderating effect of race. We found no main effect of attachment anxiety or avoidance on HPA-axis functioning. However, we found that race moderated the association between adult attachment avoidance and the CAR such that Black YSMM with higher attachment avoidance had a lower CAR as compared to White YSMM. Results suggest that there may be key differences between White and Black YSMM men's lived experiences that should be explored in future research.