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High-repetition-rate plasma-induced shockwaves in liquid have been observed using ultrafast X-ray phase contrast imaging (PCI) for the first time. Using a laser-triggered nanosecond-pulsed plasma device in heptane at ambient conditions, it is demonstrated that these well-timed weak shocks can be generated at an unprecedented repetition rate (>3 per minute), significantly faster than that of more commonly-used dynamic targets (exploding wire, gas gun). This simple portable target can easily be adapted to study discharges in different media (water, oils, solids) at comparably high repetition rates and over a wide range of possible input energies. Compared to previously PCI-imaged shocks, these shocks are relatively weak (1 < Mach number < 1.4), which advances the resolution and sensitivity limits of this high-speed imaging diagnostic. Numeric solutions of a Fresnel-Kirchhoff diffraction model are used to estimate post-shock thermodynamic conditions, the results of which show good agreement with expectations based on Rankine-Hugoniot normal shock thermodynamic relations., 5 pages, 6 figures

To differentiate peritoneal tuberculosis from carcinomatosis on computed tomography scan of abdomen, taking omental biopsy as the gold standard..This retrospective diagnostic accuracy review of cases was conducted at Aga Khan University Hospital, Karachi, and comprised patient's medical record files from February 2007 to February 2016. Computed tomography scan findings were compared with diagnosis made on the basis of histopathology. Multiple logistics regression analysis was done and sensitivity and specificity were tested through Pearson chi square test.Of the 98 patients identified, 62(63.2%)were found to be cases of disseminated tuberculosis and 36(36.7%) were diagnosed as malignant on histopathology. Computed tomography features were significantly specific to differentiate abdominal tuberculosis from carcinomatosis (p=0.004). On computed tomography,4 findings showed statistical significance: Smooth thickening of the peritoneum (p0.001), abdominal mass (p=0.03), lymph node necrosis (p=0.024) and high-density ascitic fluid (p0.001). Out of these, smooth thickening of the peritoneum (sensitivity=77%; specificity=86.1%) and high-density ascitic fluid (sensitivity=68.9%; specificity=72.2%) were more specific findings. Overall, the sensitivity and specificity of computed tomography was found to be 88.5% and 83.3%, respectively.Although no single finding on a computed tomography scan was diagnostic proof of peritoneal tuberculosis, a combination of findings could reliably distinguish between peritoneal tuberculosis and carcinomatosis. .