A 280-d study examined the effects of 17β-estradiol (E2) on reproduction and development of the sheepshead minnow (Cyprinodon variegatus) exposed from the parental (F0) through three subsequent (F1, F2, and F3) generations and evaluated the need for multigenerational assessments of the risks of endocrine-disrupting chemicals. This first three-generation study exposed adult F0 and F1 fish to mea...

Soluble mitochondrial ATPase (F1) from beef heart prepared in this laboratory contained approximately 1.8 mol of ADP and 0 mol of ATP/mol of F1 which were not removed by repeated precipitation of the enzyme with ammonium sulfate solution or by gel filtration in low ionic strength buffer containing EDTA. This enzyme had full coupling activity. Treatment of the enzyme with trypsin (5 mug/mg of F1...

(Def. 2) lenpr2(h1) = lenh1 and for every n such that n ∈ dompr2(h1) holds pr2(h1)(n) = h1(n)2. Let us consider A, B, let f1 be a homogeneous quasi total non empty partial function from A∗ to A, and let f2 be a homogeneous quasi total non empty partial function from B∗ to B. Let us assume that arity f1 = arity f2. The functor ee f1, f2dd yields a homogeneous quasi total non empty partial functi...

The experiments presented herein demonstrate that F1-parent T-B cell cooperation in vivo is significantly diminished by the addition of lymphoid cells of opposite parental type. This inhibition phenomenon is not a straightforward allosuppression mechanism as (a) it can be induced by parental lymphoid cells depleted by T cells, (b) it does not operate on cooperative interactions between homologo...

A single molecule of F1-ATPase is by itself a rotary motor in which a central gamma-subunit rotates against a surrounding cylinder made of alpha3beta3-subunits. Driven by the three betas that sequentially hydrolyse ATP, the motor rotates in discrete 120 degree steps, as demonstrated in video images of the movement of an actin filament bound, as a marker, to the central gamma-subunit. Over a bro...

Maintenance of genetic variation at loci under selection has profound implications for adaptation under environmental change. In temporally and spatially varying habitats, non-neutral polymorphism could be maintained by heterozygote advantage across environments (marginal overdominance), which could be greatly increased by beneficial reversal of dominance across conditions. We tested for revers...

F1 hybrids can outperform their parents in yield and vegetative biomass, features of hybrid vigor that form the basis of the hybrid seed industry. The yield advantage of the F1 is lost in the F2 and subsequent generations. In Arabidopsis, from F2 plants that have a F1-like phenotype, we have by recurrent selection produced pure breeding F5/F6 lines, hybrid mimics, in which the characteristics o...

OBJECTIVES The plague, which is an infectious disease caused by Yersinia pestis, still threatens many populations in several countries. The worldwide increase in human plague cases and the potential use of the bacteria as a biological weapon reinforce the need to study the immunity that is induced by potential vaccine candidates. To determine the immunogenicity of antigenic preparations based o...