TO test whether quantitative traits are under directional or homogenizing selection, it is common practice to compare population differentiation estimates at molecular markers (FST) (Wright 1951) and quantitative traits (QST) (Spitze 1993). If the trait is neutral and its determinism additive, then theory predicts that QST 1⁄4 FST, while QST . FST is predicted under directional selection for di...

Title: Central nervous system Gadolinium accumulation in patients undergoing periodical contrast MRI screening for hereditary tumor syndromes Authors: Evelynn Vergauwen ([email protected]) Anne-Marie Vanbinst ([email protected]) Carola Brussaard ([email protected]) Peter Janssens ([email protected]) Dieter De Clerck ([email protected])...

The United States stands virtually alone among leading industrialized nations in its heavy and increasing reliance on the private insurance sector to intermediate health care for its residents. The assumption underlying this system is that fierce competition among private insurers yields more efficient outcomes, broadly writ (Alain C. Enthoven 1978). However, a comprehensive survey on the state...

We present an analytical model for the cross section of a turbulent, radiative jet or wake. This model is appropriate for modeling HH jets, or “wakes” left behind by “astrophysical bullets”. Even though the model is very simple, it has the benign property of only having four free parameters (the outer radius of the beam, the axial velocity, the velocity at the edge of the beam, and the turbulen...

Subordinate males, which are excluded from reproduction often save energy by reducing their investment in sperm production. However, if their position in a dominance hierarchy changes suddenly they should also rapidly attain fertilization capability. Here, we asked how social suppression and ascension to dominance influences sperm quality, spermatogenesis and reproductive competence in the cich...

Stress assignment to polysyllabic words is the only aspect of the pronunciation of written Italian that cannot be predicted by rule. It could be a function of stress dominance in the language or of stress neighborhood (i.e., the number of words sharing an ending and a stress pattern). In two experiments, we investigated stress assignment in Italian adult and, most importantly, young readers. Wo...

In this article, we study the effect of self-fertilization on the evolution of a modifier allele that alters the recombination rate between two selected loci. We consider two different life cycles: under gametophytic selfing, a given proportion of fertilizations involves gametes produced by the same haploid individual, while under sporophytic selfing, a proportion of fertilizations involves gam...

Maps of ocular dominance and orientation in primary visual cortex have a highly characteristic structure. The factors that determine this structure are still largely unknown. In particular, it is unclear how short-range excitatory and inhibitory connections between nearby neurons influence structure both within and between maps. Using a generalized version of a well-known computational model of...

Obvious differences exist in the daily activity patterns of the LEW/Ztm and ACI/Ztm inbred strains of Laboratory rats. The inbred strain ACII Ztm shows a clear 24-h rhythm of locomotor activity. The activity pattern of the LEW/Ztm strain, however, is characterized by ultradian rhythms of 4and 4.8-h periods. Genetic analysis of crosses between the two strains was used to examine the relative amo...

Chromosomal polymorphism can be maintained by means of genic dominance, genic overdominance, recombination effects and karyotype selection. Experiments were carried out which allow us to distinguish among these factors as they effect egg hatch and larva-to-adult survival in D. subobscura. A strong karotype selection was observed. A small but highly significant recombination effect was also obse...