We investigated the overwintering biology of four temperate-latitude bark beetles: Dendroctonus frontalis Zimmermann, Ips pini (Say), I. grandicollis (Eichhoff), and I. perroti Swaine. All four species were freeze-susceptible. However, there was variation within and among species in overwintering biology that related to their geographic distribution. D. frontalis and southern populations of I. ...

The outer membrane proteins (OMPs) of Gram-negative bacterial cells, as well as the mitochondrion and chloroplast organelles, possess unique and highly stable β-barrel structures. Biogenesis of OMPs in Escherichia coli involves such periplasmic chaperones as SurA and Skp. In this study, we found that the ΔsurA Δskp double-deletion strain of E. coli, although lethal and defective in the biogenes...

to determine the effect of hen age and storage condition on egg quality, fresh eggs were sampled from two commercial flocks of white leghorn hens at 28 and 68 weeks of age. half of sampled eggs from each flock were stored at 6°c and the other half was stored at room temperature. fifteen eggs were randomly sampled from each treatment following collection and at 5-day intervals to 30 days of stor...

In a toluene-treated mutant of Escherichia coli K-12 having a temperature-sensitive, conditionally lethal mutation in the structural gene for deoxyribonucleic acid (DNA) ligase, an extensive DNA repair synthesis occurred in X-irradiated cells at the nonpermissive temperature, 42 C. At the permissive temperature, 30 C, nearly normal semiconservative synthesis and limited repair synthesis were ob...