Variable density sampling of the k-space in MRI is an integral part of trajectory design. It has been observed that data-driven trajectory design methods provide a better image reconstruction as compared to trajectories obtained from a fixed or a parametric density function. In this paper, a data-driven strategy has been proposed to obtain non-Cartesian continuous k-space sampling trajectories for MRI under the compressed sensing framework (greedy non-Cartesian (GNC)). A stochas-tic version of the algorithm (stochastic greedy non-Cartesian (SGNC)) is also proposed that reduces the computation time. We compare the proposed trajectory with a traveling salesman problem (TSP)-based trajectory and an echo planar imaging-like trajectory obtained by a greedy method called stochastic greedy-Cartesian (SGC) algorithm. The training images are taken from knee images of the fastMRI dataset. It is observed that the proposed algorithms outperform the TSP-based and the SGC trajectories for similar read-out times.
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http://dx.doi.org/10.1109/EMBC48229.2022.9871692 | DOI Listing |
Diabetes Care
January 2025
Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA.
Objective: We investigated associations between per- and polyfluoroalkyl substances (PFAS) and changes in diabetes indicators from pregnancy to 12 years after delivery among women with a history of gestational diabetes mellitus (GDM).
Research Design And Methods: Eighty Hispanic women with GDM history were followed from the third trimester of pregnancy to 12 years after delivery. Oral and intravenous glucose tolerance tests were conducted during follow-up.
Account Res
January 2025
Department of Methodology and Statistics, School of Social and Behavioural Sciences, Tilburg University Prof. Cobbenhagenlaan, Tilburg, The Netherlands.
Background: Supervision is one important means of promoting responsible research. However, what a responsible supervisor should do and how to foster a responsible supervisory climate is unclear.
Methods: Between January 2023 and February 2024, I conducted 17 focus groups in The Netherlands and Denmark with 85 PhD candidates and PhD supervisors to understand what practices supervisors engage in to promote responsible conduct of research and what strategies could promote a responsible supervisory relationship.
Gerontologist
January 2025
Department of Sociology, Yale University, 493 College Street, New Haven, CT, 06511, USA.
Background And Objectives: The heterogeneity of population-based trajectories of care recipients' (CRs) cognitive functioning and how they are associated with their caregivers' mental health is less studied in the United States. Informed by the stress process model, this study examines the relationship between care recipients' cognitive trajectories and caregivers' depressive symptoms, and the mediating role of caregiving burden.
Research Design And Methods: Data were from the National Health and Aging Trends Study (2011-2020) for 1,086 care recipients and their 1,675 caregivers from the 2021 National Study of Caregiving.
Glob Chang Biol
January 2025
Scripps Institution of Oceanography, UC San Diego, La Jolla, California, USA.
High spatial or temporal variability in community composition makes it challenging for natural resource managers to predict ecosystem trajectories at scales relevant to management. This is commonly the case in nearshore marine environments, where the frequency and intensity of disturbance events vary at the sub-kilometer to meter scale, creating a patchwork of successional stages within a single ecosystem. The successional stage of a community impacts its stability, recovery potential, and trajectory over time in predictable ways.
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October 2024
State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology Visual Science, Guangzhou 510060, China.
The ocular surface ectoderm (OSE) is essential for the development of the ocular surface, yet the molecular mechanisms driving its differentiation are not fully understood. In this study, we used single-cell transcriptomic analysis to explore the dynamic cellular trajectories and regulatory networks during the differentiation of embryonic stem cells (ESCs) into the OSE lineage. We identified nine distinct cell subpopulations undergoing differentiation along three main developmental branches: neural crest, neuroectodermal, and surface ectodermal lineages.
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