White-throated sparrows (Zonotrichia albicollis) exhibit a genetic polymorphism that affects plumage and behavior in both sexes. White-striped morphs are more territorially aggressive, whereas tan-striped morphs provision nestlings at a higher rate. We investigated testosterone physiology in this species in an effort to understand hormonal mechanisms for the observed differences in aggression a...

We study spin and charge striped states at the half-filled high Landau level in the zero Zeeman energy limit using a HartreeFock approximation. It is shown that a ferromagnetic striped Hall state is more stable than the antiferromagnetic striped state or charge striped state. We calculate the collective excitations using the single mode approximation.

abstract background: the aims of this study were to assay the activity of adenosine deaminase (ada) in estrogen receptor positive (mcf-7) and negative (mda-mb468) breast cancer cell lines. methods: mda-mb468 and mcf-7 breast cancer cell lines were cultured in complete medium, striped serum with and without 0.0 1~-lm diethylstilbestrol (des), complete medium in the presence and absence of 111m t...

According to conceptual models, the distribution of resources plays a critical role in determining how organisms distribute themselves near habitat edges. These models are frequently used to achieve a mechanistic understanding of edge effects, but because they are based predominantly on correlative studies, there is need for a demonstration of causality, which is best done through experimentati...

The current work describes two new species of Gyrodactylus von Nordmann, 1832 collected from pipefish Syngnathus scovelli (Evermann et Kendall) and Syngnathus typhle L. during two separate gyrodactylosis episodes on fish held in a public aquarium located in northern Italy. The gyrodactylids collected from the skin, fins and gills of pipefish were subjected to a morphological analysis of the att...

Species exhibiting sex-role reversal provide an unusual perspective on the evolution of sex roles and sex differences. However, the proximate effects of sex-role reversal are largely unknown. Endocrine disruptors provide an experimental mechanism to address hormonal regulation of sexually dimorphic gene expression in sex-role-reversed taxa. Here, we investigate gene expression patterns in the l...

The striped mullet (Mugil cephalus L.) is distributed circumglobally in tropical and semitropical waters between latitudes 42°N and 42°S (Thomson, 1963; Rossi et al., 1998). Even though considered a marine species, striped mullet are euryhaline and can be found year round throughout the full range of estuarine salinities in the southeastern United States (Jacot, 1920; Anderson, 1958). Striped m...

Background. Syngnathid fishes produce three kinds of sounds, named click, growl and purr. These sounds are generated by different mechanisms to give a consistent signal pattern or signature which is believed to play a role in intraspecific and interspecific communication. Commonly known sounds are produced when the fish feeds (click, purr) or is under duress (growl). While there are more acoust...