Changes in nerve root compression forces with spinal motion were measured on six freshly frozen adult cadaver spine specimens. A model was devised to represent a herniated disc at the L4-5 level. ...This was done using an anterior approach placing a compression-measuring device through the disc at the L4-5 level and against the L5 root. An accelerometer was used to monitor the range of motion of the spine. Because the compression device was held in a static position, the only variable was the tautness of the nerve root across the tip of the device. By simultaneously monitoring motion and force delivered at the tip of the compression meter placed at the nerve root, we were able to quantitate nerve root tension forces across the tip of the measuring device in relation to spinal motion. The force was measured with controls as well as in flexion and extension. In addition, the force was measured as traction was applied to the L5 root. The amount of compressive force and tension in the nerve root increased with flexion of the spine and decreased with extension of the spine. In conclusion, flexion of the lumbar spine increased the compressive force on the L5 root and extension decreased the compressive force on the L5 root.
The International Association of Aquatic and Marine Science Libraries and Information Centers (IAMSLIC), comprised of 325 members from 86 countries, has a long history of resource sharing based on ...personal connections among its members. In 2002, IAMSLIC developed a resource-sharing system using a unified search interface that relies on Z39.50 broadcast search capabilities to query individual catalogs. In addition to the IAMSLIC Z39.50 Distributed Library, which searches standard OPAC catalogs, smaller libraries can share library holdings through the online Union List of Marine and Aquatic Serials. Member libraries may submit interlibrary loan requests for items located through either avenue. This successful program may serve as a model for other library organizations interested in sharing resources and extending access to subject-specific materials amongst member libraries.
The cardiovascular responses to tracheal intubation using a fibreoptic bronchoscope or Macintosh laryngoscope were compared in twenty in-patients and twenty day-stay patients. Within these groups ...patients were randomly allocated to direct laryngoscopic or fibreoptic bronchoscopic intubation. Arterial blood pressure, heart rate and arterial oxygen saturation were recorded before induction and at one-minute intervals until four minutes after intubation. In both groups both laryngoscopic and bronchoscopic intubation resulted in a significant rise in blood pressure and heart rate. At no stage was there a significant difference in mean blood pressure in either group, or in heart rate in the day-stay patients, between the different methods of intubation. In the in-patients mean heart rate was significantly higher in those patients intubated with the bronchoscope at three and four minutes after intubation. Time taken for intubation was significantly longer in those patients intubated with the bronchoscope. In no patient did the arterial oxygen saturation fall below 98%.
Here, we study the OEDGE code that is used to model the outer divertor plasma for discharges from a density scan experiment on DIII-D with the objective of assessing EIRENE and ADAS hydrogenic ...emission atomic physics data for Dα, Dβ and Dγ for values of Te and ne characteristic of the range of divertor plasma conditions from attached to weakly detached. Confidence in these values is essential to spectroscopic interpretation of any experiment or modeling effort. Good agreement between experiment and calculated emissions is found for both EIRENE and ADAS calculated emission profiles, confirming their reliability for plasma conditions down to ~1 eV. Lastly, for the cold dense plasma conditions characteristic of detachment, it is found that the calculated emissions are especially sensitive to Te.
Recently, both Alcator C-Mod and DIII-D tokamaks observed fast anomalous cross-field plasma transport in the SOL. These observations supported by theoretical studies have indicated that such ...transport is essentially non-diffusive and intermittent. We present the results of macroscopic plasma simulations with the UEDGE transport code including anomalous cross-field outward-directed convection for a series of low-power DIII-D shots. Our analysis of experimental and simulation data supports the view that non-diffusive transport is important for the entire edge plasma behavior in both L- and H-mode discharges.
•Measured localized erosion and redeposition of Aluminum in DIII-D divertor plasmas.•Modeled multi-step material migration across surfaces with different morphologies.•Graphite surface roughness ...leads to enhanced accumulation of Al deposits.•Experiments show asymmetry in re-deposition that is not reproduced by existing models.
We present measurements and modeling of aluminum erosion and redeposition experiments in separate helium and deuterium low power, low density L-mode plasmas at the outer divertor strike point of DIII-D to provide a low-Z material benchmark dataset for tokamak erosion-deposition modeling codes. Coatings of Al ∼100nm thick were applied to ideal (smooth) and realistic (rough) surfaces and exposed to repeat plasma discharges using the DiMES probe. Redeposition in all cases was primarily in the downstream toroidal field direction, evident from both in-situ spectroscopic and post-mortem non-spectroscopic measurements. The gross Al erosion yield was estimated from film thickness change measurements of small area samples, and was found to be ∼40–70% of the expected erosion yield based on theoretical physical sputtering yields after including sputtering by a 1–3% carbon impurity. The multi-step redeposition and re-erosion process, and hence the measured net erosion yield and material migration patterns, were found to be influenced by the surface roughness and/or porosity. A time-dependent model of material migration accounting for deposit accumulation in hidden areas was developed to reproduce the measurements in these experiments and determine a redeposition probability distribution function for sputtered atoms.
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