Axial filament formation in Bacillus subtilis: induction of nucleoids of increasing length after addition of chloramphenicol to exponential-phase cultures approaching stationary phase.

When chloramphenicol was added to a culture of Bacillus subtilis in early exponential growth, microscopic observation of cells stained by 4',6-diamidino-2-phenylindole showed nucleoids that had changed in appearance from irregular spheres and dumbbells to large, brightly stained spheres and ovals. In contrast, the addition of chloramphenicol to cultures in mid- and late exponential growth showed cells with elongated nucleoids whose frequency and length increased as the culture approached stationary phase. The kinetics of nucleoid elongation after the addition of chloramphenicol to exponential-phase cultures was complex.

The pop-out, pull-through suture technique.

New suturing techniques have continually been developed through the years out of a need to provide a more pleasing scar, provide an easier method, or to enhance patient comfort and satisfaction. This article details the pop-out, pull-through suture.

Buoyant density studies of several mecillinam-resistant and division mutants of Escherichia coli.

The buoyant density of wild-type Escherichia coli cells has previously been reported not to vary with growth rate and cell size or age. In the present report we confirm these findings, using Percoll gradients, and analyze the recently described lov mutant, which was selected for its resistance to mecillinam and has been suggested to be affected in the coordination between mass growth and envelope synthesis. The average buoyant density of lov mutant cells was significantly lower than that of wild-type cells.

Relationship between changes in buoyant density and formation of new sites of cell wall growth in cultures of streptococci (Enterococcus hirae ATCC 9790) undergoing a nutritional shift-up.

When the glutamate concentration of cultures of Enterococcus hirae was raised from 20 to 300 micrograms/ml, the mass doubling time decreased from ca. 85 to 45 min in 9 min, but balanced growth was not reestablished for 30 to 40 min. During the unbalanced period of growth, RNA and protein synthesis proceeded more rapidly than did peptidoglycan synthesis, buoyant density increased from ca.

Variation in buoyant density of whole cells and isolated cell walls of Streptococcus faecium (ATCC 9790).

The buoyant density of whole cells of Streptococcus faecium varies with growth rate and during the cell cycle. Two possible explanations for this were explored: (i) the density of cell walls may vary, and (ii) the proportions of wall and cytoplasm may vary. We tested the first possibility by isolating walls from chilled, unfixed populations of S.

American fertility in transition: new estimates of birth rates in the United States, 1900-1910.

This article presents new estimates of age-specific overall and marital fertility rates for the entire United States for the period 1900-1910. The estimation techniques are the two-census parity increment method and the own-children method. The data sources are the 1900 census public use sample and tabulations of 1910 census fertility data published with the 1940 census.

The effect of date of cut and barley substitution on gain and on the efficiency of utilization of grass silage by growing cattle. 2. Nutrient supply and energy partition.

1. The effect of harvesting date of perennial ryegrass (Lolium perenne) on the nutritive value of the resultant silage and the effect of substitution of late-cut silage with barley was examined in growing cattle. The diets comprised early-cut (H) and late-cut (L) silage offered alone or with 280 (LC1) or 560 (LC2) g rolled barley/kg total dry matter (DM) substituted for late-cut silage.

The digestion of perennial ryegrass (Lolium perenne cv. Melle) and white clover (Trifolium repens cv. Blanca) by grazing cattle.

1. Pure swards of perennial ryegrass (Lolium perenne cv. Melle) as a primary growth (May), trimmed primary growth (early June) and regrowth (late June), and white clover (Trifolium repens cv.

Systemic mycosis due to Penicillium marneffei in a patient with antibody to human immunodeficiency virus.

Systemic mycosis due to Penicillium marneffei is described in a man infected with human immunodeficiency virus and who had travelled in S.W. China.

Effect of forage species and season on nutrient digestion and supply in grazing cattle.

1. A total of twenty Friesian steers were grazed on pure swards of either perennial ryegrass (Lolium perenne cv. Melle) or white clover (Trifolium repens cv.

The efficiency of energy utilization in growing cattle consuming fresh perennial ryegrass (Lolium perenne cv. Melle) or white clover (Trifolium repens cv. Blanca).

1. Twenty Friesian steers (225 kg live weight) were fed on mid- (M) (June-July) and late- (L) (August-September) season crops of either fresh perennial ryegrass (Lolium perenne cv. Melle) (G) or white clover (Trifolium repens cv.