Geoffrey C. Collins, James W. Head, Jeffrey M. Moore, and Paul M. Schenk, LASP, University of Colorado, Box 392, Boulder, CO 80309 ([email protected]), Astronomy and Physics Dept., Wheaton College, Norton, MA 02766, Brown University, Box 1846, Providence, RI 02912, Ames Research Center, MS 245-3, Moffett Field, CA, 94035, Lunar and Planetary Institute, 3600 Bay Area Blvd, Houston, ...

Tracheostomy tubes are used to administer positive-pressure ventilation, to provide a patent airway, and to provide access to the lower respiratory tract for airway clearance. They are available in a variety of sizes and styles from several manufacturers. The dimensions of tracheostomy tubes are given by their inner diameter, outer diameter, length, and curvature. Differences in dimensions betw...

Many intracellular compartments of eukaryotic cells do not adopt a spherical shape, which would be expected in the absence of mechanisms organizing their structure. However, little is known about the principles determining the shape of organelles. We have observed very defined structural changes of vacuoles, the lysosome equivalents of yeast. The vacuolar membrane can form a large tubular invag...

INTRODUCTION Conventional Vacutainer® Sodium Citrate blood collection tubes contain a relatively high concentration of contaminating magnesium ions, which may result in shortening of the prothrombin time (PT) and the International Normalized Ratio (INR). Recently the manufacturer of Vacutainer® Sodium Citrate tubes introduced new tubes with a magnesium-poor stopper. The magnesium concentration ...