The ribosomes of mouse ova were labeled by exposure of growing ovarian oocytes to [3H]uridine. The ribosomes of ova lysed and dispersed in hypotonic medium were contained in particles with an unusually low buoyant density in CsCl density gradients. These particles sedimented at 9000g or less, and electron microscopy of the pellet revealed ribosome-like particles embedded in a fibrillar network....

Density changes of aerosol particles as a result of chemical reaction Y. Katrib, S. T. Martin, Y. Rudich, P. Davidovits, J. T. Jayne, and D. R. Worsnop Division of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, UK Department of Environmental Sciences, Weizmann Institute, Rehovot 76100, Israel Chemistry Department, Boston College, Chestnut Hill, MA 02467, USA Aerodyne...

At onset of egg-laying in the chicken, plasma levels of apolipoprotein VLDL-II (apoII) increase dramatically, suggesting a function of apoII in yolk deposition of triglyceride-rich lipoproteins. Thus, the possibility that this female-specific homodimeric protein (Mr of subunit, 9500) is recognized by the oocyte receptor for low and very low density lipoproteins was investigated. ApoII was purif...

CONTEXT Plasma phospholipid transfer protein mediates the transfer of phospholipids from triglyceride-rich lipoproteins, very low density lipoproteins and low density lipoproteins to high density lipoproteins, a process that is also efficient between high density lipoprotein particles. It promotes a net movement of phospholipids, thereby generating small lipid-poor apolipoprotein AI that contai...

The rearrangement of plasma due to turbulence is among the most important processes that occur in planetary magnetospheres and in experiments used for fusion energy research. Remarkably , fluctuations that occur in active magnetospheres drive particles inward and create centrally peaked profiles. Until now, the strong peaking seen in space has been undetectable in the laboratory because the los...

We present a simple model for an associating liquid in which polymorphism and density anomaly are connected. Our model combines a two dimensional lattice gas with particles interacting through a soft core potential and orientational degrees of freedom represented through thermal "ice variables." The competition between the directional attractive forces and the soft core potential leads to a pha...

Downward carbon flux in the ocean is largely governed by particle settling. Most marine particles settle at low Reynolds numbers and are highly porous, yet the fluid dynamics of this regime have remained unexplored. We present results of an experimental investigation of porous particles settling through a density interface at Reynolds numbers between 0.1 and 1. We tracked 100 to 500 μm hydrogel...

BACKGROUND Apoprotein B-containing lipoproteins are atherogenic, but atheroprotective functions of apoprotein A-containing high-density lipoprotein (HDL) particles are poorly understood. The association between lipoproteins and plaque components by coronary computed tomography angiography (CTA) and intravascular ultrasound with radiofrequency backscatter (IVUS/VH) has not been evaluated. METH...