Over this stress range, the behavior of z-cut quartz under shock compression [J.
Appl. Phys. 88, 5671 (2000)] is nonlinear elastic and in good agreement with predictions based on the measured values of the second and third order elastic constants. In-material and free surface velocities were measured in the present work and analyzed, using a Lagrangian analysis, to provide a continuous loading curve for z-cut quartz. The wavelet speed-particle velocity (C(u)-u, where C(u)equivalent to(Delta h/Delta t)(u)) results were somewhat sensitive to the CPPG panel design details, as well as the velocity data acquisition and reduction see more techniques. Improvements to provide optimal data were discussed and used to provide accurate longitudinal stress-density response to 7 GPa (6% density compression). The C(u)-u curves, a more stringent measure of the material response to nonlinear compression, were within 0.6% of the values predicted using shock compression measurements. This excellent agreement demonstrates that the shockless selleck chemicals llc compression response of quartz is indistinguishable from the shock response in the nonlinear elastic regime and provides a good foundation for comparing the inelastic response
of solids under shockless and shock compression. The present work also demonstrated the use of the CPPG as a laboratory capability for examining the shockless compression of materials.”
“Objective: Since 2000, we have used
the Moncrief-Popovich technique as our standard method for peritoneal dialysis (PD) catheter insertion. The subcutaneous portion of the catheter is externalized immediately before initiation of PD. We undertook the present review to investigate whether duration of catheter embedment affects catheter or patient outcome.
Methods: All catheters inserted beginning 1 January 2000 and externalized by 31 December 2008 were included. The primary outcome was catheter survival. Secondary outcomes were catheter patency (no fibrin plug or omental wrap) and complications within 90 days after externalization. A standard peritoneal equilibration test was SCH727965 concentration used to classify peritoneal membrane transport status. Proportional hazards regression models were used to test whether duration of embedment affected catheter outcomes. The models treated embedment duration as both a continuous predictor and a categorical predictor categorized by tertile.
Results: A total of 134 catheters were implanted and externalized. Twelve patients received 2 catheters each. To ensure statistical independence of the observations, 12 of the latter 24 catheters were excluded (1 chosen randomly from each patient), resulting in a useable sample size of 122 catheters. The total duration of observation was 2359 patient-months. The median duration of catheter embedment was 40.5 days (range: 2 – 788 days).