BACKGROUND Electronic clocks exhibit undesirable jitter or time variations in periodic signals. The circadian clocks of humans, some animals, and plants consist of oscillating molecular networks with peak-to-peak time of approximately 24 hours. Clockwork orange (CWO) is a transcriptional repressor of Drosophila direct target genes. METHODOLOGY/PRINCIPAL FINDINGS Theory and data from a model o...

Soil samples with temperatures up to 64 degrees C were collected from Mount Erebus, an active volcano located on Ross Island, Antarctica. Acridine orange direct counts and most probable number counts of soil samples stored at 4 degrees C for 2 months showed a wide variation in the number of thermophilic microorganisms in different soils. Organisms similar to Clostridium thermohydrosulfuricum, B...

Behavioral interactions between coexisting species may reflect underlying ecological interactions or may arise from factors unrelated to ecological interactions between species. We examined behavioral interactions between two coexisting, migratory wood warblers that competitively interact on breeding territories in central Arizona, USA. The larger Orange-crowned Warbler (Vermivora celata) is ag...

Electrocrystallization of the (S,S,S,S) enantiomer of tetramethyl-bis(ethylenedithio)tetrathiafulvalene donor 1 in the presence of the dianionic hexanuclear rhenium (III) cluster [Re6S6Cl8]2 ́ affords a crystalline radical cation salt formulated as [(S)-1]2 ̈Re6S6Cl8, in which the methyl substituents of the donors adopt an unprecedented all-axial conformation. A complex set of intermolecular TTF ̈...

Dialuminiummacrocycles based on bisglyoximato moieties were prepared and their coordination chemistry with Fe(II) and Pd(II) was investigated. The bridging aluminium centers were supported by several types of tetradentate diphenoxide diamine ligands. The nature of the ancillary ligands bound to aluminium was found to affect the overall geometry and symmetry of the metallomacrocycles. Enantiopur...

Freezing-thawing effects on the nuclei of porcine and human spermatozoa were studied by determining native DNA percentage from fluorescence after acridine orange (AO) staining and by analyzing chromatin structure by a quantitative microspectrophotometric study of Feulgen-DNA complexes before and after freezing. The study of boar spermatozoa revealed no alteration in native DNA percentage after ...

In the present work, the effect of initial pH of methylene blue solution on the kinetics of dye sorption from synthetic aqueous solution by a natural waste material namely: orange peels, was studied. Kinetic data were measured in batch conditions. Methylene blue uptake was time contact and solution initial pH dependent. Maximum dye sorption was found to occur at initial pH 9. Two simplified kin...

A dynamic combinatorial library of metal-dye complexes was obtained by reacting aqueous solutions of the dyes Methyl Calcein Blue, Arsenazo I, and Xylenol Orange with CuCl(2) and NiCl(2). The mixture gave a characteristic UV-Vis response upon addition of the peptide hormones angiotensin I and angiotensin II. This allowed distinguishing pure samples of peptide hormones from mixtures. The discrim...

Kahn, Phyllis L. (Princeton University, Princeton, N.J.), and Donald R. Helinski. Relationship between colicinogenic factors E(1) and V and an F factor in Escherichia coli. J. Bacteriol. 88:1573-1579. 1964.-Colicinogenic factors are the genetic determinants for colicin production in enteric bacteria. An examination of the relationship of two colicinogenic factors, colE(1) and colV, to the F fac...

Schistosoma mansoni eggs are classified, according to morphological characteristics, as follows: viable mature and immature eggs; dead mature and immature eggs, shells and granulomas. The scope of this study was to compare the staining characteristics of different morphological types of eggs in the presence of fluorescent labels and vital dyes, aiming at differentiating live and dead eggs. The ...