The purpose of this study was to develop a spiral-based combined spin-and gradient-echo (spiral-SAGE) method for simultaneous dynamic contrast-enhanced (DCE-MRI) and dynamic susceptibility contrast MRI (DSC-MRI). Methods: Using this sequence, we obtained gradient-echo TEs of 1.69 and 26 ms, a SE TE of 87.72 ms, with a TR of 1663 ms. Using an iterative SENSE reconstruction followed by deblurring, spiral-induced image artifacts were minimized. Healthy volunteer images are shown to demonstrate image quality using the optimized reconstruction, as well as for comparison with EPI-based SAGE. A bioreactor phantom was used to compare dynamic-contrast time courses with both spiral-SAGE and EPI-SAGE. A proof-of-concept cohort of patients with brain tumors shows the range of hemodynamic maps available using spiral-SAGE. Results: Comparison of spiral-SAGE images with conventional EPI-SAGE images illustrates substantial reductions of image distortion and artifactual image intensity variations. Bioreactor phantom data show similar dynamic contrast time courses between standard EPI-SAGE and spiral-SAGE for the second and third echoes, whereas first-echo data show improvements in quantifying T 1 changes with shorter echo times. In a cohort of patients with brain tumors, spiral-SAGE-based perfusion and permeability maps are shown with comparison with the standard single-echo EPI perfusion map. Conclusion: Spiral-SAGE provides a substantial improvement for the assessment of perfusion and permeability by mitigating artifacts typically encountered with EPI and by providing a shorter echo time for improved characterization of permeability.

This work shows the extent of bias in cerebrospinal fluid flow quantification due to radiofrequency saturation effects. This clinical relevance of this error was presented with respect to shunt responsiveness among normal pressure hydrocephalus patients. Magn Reson Med 79:2067-2076, 2018. © 2017 International Society for Magnetic Resonance in Medicine.

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A reconfigurable robotic gripper based on pneumatic technology has been designed and developed for grasping fabric materials in garment industries automation. The design is based on reconfigurable multidegree of freedom, which can manipulate single and multiple panels of limp materials. The design consist of four arms initially in a cross bar configuration, hosting four suction cups mounted on each of the arms. The design assures low inertia, high modularity and full flexibility adapting to the picking of limp materials in garment and shoe industries. The simulation referring to a worst-case operative cycle has been performed in the environment of a current industrial layout. The kinematic and dynamic performance of the gripper system is analyzed in ADAMS simulation software and the results are presented. The architecture of the gripper is simple and the choice of pneumatic actuators improves the reliability of the system.

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