Multi-contrast 4DMR via MR multitasking: Early clinical experience and implication for liver stereotactic body radiation therapy.

Background: Liver tumors have low contrast on 4DCT. A novel Multitasking (MT)MR imaging technique has been implemented on the MR simulator, providing both T1 and T2-weighted 4DMR images in a single 8-min free-breathing scan for better tumor delineation and motion evaluation. This study reports our early clinical experience of MTMR regarding tumor visibility, motion characteristics, and resultant dosimetry compared to post-contrast 4DCT for liver SBRT.

Seeded stimulated X-ray emission at 5.9 keV.

X-ray free-electron lasers (XFELs) provide intense pulses that can generate stimulated X-ray emission, a phenomenon that has been observed and studied in materials ranging from neon to copper. Two schemes have been employed: amplified spontaneous emission (ASE) and seeded stimulated emission (SSE), where a second color XFEL pulse provides the seed. Both phenomena are currently explored for coherent X-ray laser sources and spectroscopy.

Does Practice Type Determine the Complexity of Patients Encountered for Orthognathic Surgery?

Purpose: This study sought to determine whether the type of oral and maxillofacial surgery (OMS) practice dictated the complexity of patients encountered for orthognathic surgery and to determine whether there were meaningful differences in comorbidities between patient groups.

Materials And Methods: This was a retrospective cohort study of orthognathic surgical patients operated on by surgeons at an academic medical center (AMC; OMS department at the University of Alabama-Birmingham) compared with a private practice (PP) group that also operated at the AMC auxiliary facility. Surgical procedures included in this study were Le Fort osteotomy, bilateral sagittal split osteotomy, genioplasty, and combinations of these procedures.

Influence of connection geometry on dynamic micromotion at the implant-abutment interface.

The aim of this study was to evaluate dynamic micromotion at the implant-abutment interface for 3 different implant neck designs. Five samples each from 3 implant types with different neck designs were subjected to 1 x 10(6) cycles under simulated oral conditions. Load magnitudes varied from 10 to 250 N at 15 Hz.