There is a need for valves and pumps that operate at the microscale with precision and accuracy, are versatile in their application, and are easily fabricated. To that end, we developed a new rotary planar multiport valve to faithfully select solutions (contamination = 5.22 ± 0.
View Article and Find Full Text PDFAdvances in scientific instrumentation have allowed experimentalists to evaluate well-known systems in new ways and to gain insight into previously unexplored or poorly understood phenomena. Within the growing field of multianalyte physiometry (MAP), microphysiometers are being developed that are capable of electrochemically measuring changes in the concentration of various metabolites in real time. By simultaneously quantifying multiple analytes, these devices have begun to unravel the complex pathways that govern biological responses to ischemia and oxidative stress while contributing to basic scientific discoveries in bioenergetics and neurology.
View Article and Find Full Text PDFOBJECTIVE. Imaging provides evidence for the response to oncology treatment by the serial measurement of reference lesions. Unfortunately, the identification, comparison, measurement, and documentation of several reference lesions can be an inefficient process.
View Article and Find Full Text PDFRationale And Objectives: The aim of this study was to determine whether key radiology report "consumers" in our institution prefer structured measurement reporting in a dedicated report section over the current practice of embedding measurements throughout the "Findings" section, given the availability of new tools for quantitative imaging interpretation that enable automated structured reporting of measurement data.
Materials And Methods: Oncologic clinicians and radiologists at our institution were surveyed regarding their preferences for a standard report versus three reports each having uniquely formatted dedicated "Measurements" sections and regarding their impressions of various characteristics of report quality demonstrated by these reports. The online survey was completed by 25 radiologists, 16 oncologists, and 17 oncology nurses and research assistants (registrars).
Objective: We sought to investigate differences in indices of pulsatility between patients with normal ventricular function and patients with heart failure studied at the time of implantation with continuous-flow or pulsatile-flow left ventricular assist devices.
Methods: Eight patients with normal ventricular function and 22 patients with heart failure were studied. A high-fidelity aortic and left ventricular pressure catheter was inserted retrograde through the aortic valve into the left ventricle, and transit-time flow probes were placed on the aorta and device outflow graft.
Magn Reson Med
September 2005
T1 and T2 relaxation of excised frog sciatic nerve water was characterized at 7 T. Based on these findings, optimal timings for multiple inversion-recovery magnetization preparations were determined to selectively excite the so-called myelin-water T2 component. Subsequent double inversion-recovery and triple inversion-recovery preparations were used in combination with CPMG acquisitions to experimentally determine optimal timings and effect of the preparation.
View Article and Find Full Text PDFDiffusion tensor MRI tractography aims to reconstruct noninvasively the 3D trajectories of white matter fasciculi within the brain, providing neuroscientists and clinicians with a potentially useful tool for mapping brain architecture. While this technique is widely used to visualize white matter pathways, the associated uncertainty in fiber orientation and artifacts have, to date, not been visualized in conjunction with the trajectory data. In this work, the bootstrap method was used to determine the distributions of diffusion indices such as trace and anisotropy, together with the uncertainty in fiber orientation.
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