High-affinity pathologic rheumatoid factor (RF) B cells occur in autoimmune diseases such as rheumatoid arthritis, but are deleted in healthy individuals. The reasons for the survival and differentiation of these autoreactive B cells in rheumatoid arthritis are not known. Previous studies in mice transgenic for a human IgM RF have shown that peripheral encounter with soluble human IgG leads to ...

Physiological studies of visual attention have demonstrated that focusing attention near a visual cortical neuron's receptive field (RF) results in enhanced evoked activity and RF shift. In this work, we explored the mechanisms of attention induced RF shifts in cortical network models that receive an attentional 'spotlight'. Our main results are threefold. First, whereas a 'spotlight' input alw...

IMPORTANT PREAMBLE • RF Interactions impacts the vast majority of components involved in RF Transmit and RF Receive chains in an MR system. • This lecture, however, will deliberately focus on RF Interactions occurring at the level of a sample imaged with Receive and/or Transmit RF Coil Arrays consisting of multiple Receive and/or Transmit RF Coil Elements driven by individual RF Channels. • Thi...

BACKGROUND Improved understanding of rod fracture (RF) in adult spinal deformity could be valuable for implant design, surgical planning, and patient counseling. OBJECTIVE To evaluate symptomatic RF after posterior instrumented fusion for adult spinal deformity. METHODS A multicenter, retrospective review of RF in adult spinal deformity was performed. Inclusion criteria were spinal deformit...

OBJECTIVES To investigate differences in response to tumor necrosis factor inhibitor treatment (TNFi) in seropositive (rheumatoid factor positive; RF+) versus seronegative (RF-) patients with established RA as measured by the Health Assessment Questionnaire Disability Index (HAQ-DI) and pain. METHODS RA patients from an established RA cohort were studied according to rheumatoid factor (RF) st...

Wave propagation effects diminish the quality of MR images at main fields of 3T or above. Parallel RF transmission has the potential of compensating for these effects through RF shimming. RF shimming can be performed in two different ways. The basic way of RF shimming is to adjust the global amplitude and phase of the currents in each transmit element, aiming at a constant B1 in the region of i...

due to urbanization and population increase, need for metro tunnels, has been considerably increased in urban areas. estimating the surface settlement caused by tunnel excavation is an important task especially where the tunnels are excavated in urban areas or beneath important structures. many models have been established for this purpose by extracting the relationship between the settlement a...