The host suitability of 64 commercial corn hybrids for a Meloidogyne arenaria race 2 population and a M. incognita race 4 population was determined in greenhouse experiments. 'Northrup King 508' and 'Pioneer Brand 3147' maintained M. arenaria below and at the initial population level, respectively, indicating that these hybrids are relatively poor hosts for this species. RF values (final egg nu...

An effective medium treatment is used to extend Berg and Purcell's theory of diffusion-controlled ligand binding to a sphere partially covered by receptors. This treatment takes into account more completely the effects of interference between receptors. The results are in excellent agreement with computer simulations by Northrup.

aCalifornia Institute of Technology, 1200 E. California Drive, Pasadena, California 91125, USA bCurrently with the Jet Propulsion Laboratory, 4800 Oak Grove Dr., Pasadena, California 91109, USA cCurrently with Northrup Grumman Aerospace Systems, One Space Park Dr., Redondo Beach, California 90278, USA dCurrently with The Charles Stark Draper Laboratory, Inc., 555 Technology Square, Cambridge, M...

INTRODUCTION The solid propellant industry has until recently used the MSA particle size analyzer for the analysis of superfine materials. Since MSA equipment is no longer manufactured and MSA test time is fairly lengthy in the superfine region, other methods were investigated by Atlantic Research Corporation. After investigating several instruments, it was decided that the Microtrac small part...

Received Oct 2, 1998. Received revised Jan 13, 1999. Accepted for publication Jan 13, 1999. From the Division of Child Neurology, University of Texas Southwestern Medical Center at Dallas (Dr Roach), Dallas, TX; the Division of Pediatric Neurology, University of Connecticut at Connecticut Children’s Medical Center (Dr DiMario), Hartford, CT; the Johnson Neurological Clinic (Dr Kandt), High Poin...

to a Leeds and Northrup Cleretrend 12 point recorder, provision being made for matching the photocell outputs. The recorder selects each channel in turn and prints a dot corresponding to the deflection from that channel. At the paper speed of 3 in. per hour the resultant trace is a continuous line. Channel identification is by colour and number. This type of recorder was chosen after careful co...