For over 10 years, MACLISP has supported a variety of projects at M.I.T.'s Artificial Intelligence Laboratory, and the Laboratory for Computer Science (formerly Project MAC). During this time, there has been a continuing development of the MACLISP system, spurred in great measure by the needs of MACSYMA development. Herein are reported, in a mosiac, historical style, the major features of the s...

Theiler's murine encephalomyelitis virus (TMEV) is a highly cytolytic picornavirus that persists in the mouse central nervous system (CNS) largely in macrophages with infection maintained by macrophage-to-macrophage spread. Infected macrophages in the CNS undergo apoptosis. We recently showed that M1-D macrophages infected with the low-neurovirulence TMEV BeAn virus became apoptotic through the...

density-gradient centrifugation. ISCO fractionator scanning patterns indicated a high degree of purity but serological results revealed the presence of some host contaminates. The yield of virus was abeut 2mgfleOg of bro'ad bean leaves. The titer of the antiserum against isolate No. 30 was 1!2048 by ring precipitin tests. Although the iutact virus particles could n6t diffuse in agar gel plates,...

Cliver, D. O. 1988. Virus transmission via foods. Food Technol. 42:241-248. Viruses have “emerged” as causes of foodborne disease, according to data compiled by the Centers for Disease Control and Prevention. During 1983–87 in the United States, Norwalk virus was the fifth leading cause of foodborne disease among outbreak-associated illnesses; hepatitis A virus was the sixth; and other viruses ...

Viruses are most frequently discovered because they cause disease. To expand knowledge of plant-associated viruses beyond these narrow constraints, non-cultivated plants of the Tallgrass Prairie of the United States were systematically surveyed for evidence of viruses. This report discusses putative viruses of the family Secoviridae identified by the survey. Sequence analysis suggests the prese...

Now, as before, transmission electron microscopy (TEM) is a widely used technique for the determination of virions size. In some studies, dynamic light scattering (DLS) has also been applied for this purpose. Data obtained by different authors and using different methods could vary significantly. The process of TEM sample preparation involves drying on the substrate, which can cause virions to ...