Large-scale multilocus studies have become common in molecular phylogenetics, but the best way to interpret these studies when their results strongly conflict with prior information about phylogeny remains unclear. An example of such a conflict is provided by the ratites (the large flightless birds of southern land masses, including ostriches, emus, and rheas). Ratite monophyly is strongly supp...

Computer techniques readily extract from the brainwaves an orderly sequence of brain potentials locked in time to sound stimuli. The potentials that appear 8 to 80 msec after the stimulus resemble 3 or 4 cycles of a 40-Hz sine wave; we show here that these waves combined to form a single, stable, composite wave when the sounds are repeated at rates around 40 per sec. This phenomenon, the 40-Hz ...

Spatiotemporally organized waves are among the most ubiquitous activity patterns in the brain. Recent advances in electrophysiology, imaging, and other technologies allow experimentalists to observe these activity patterns simultaneously in the responses of many individual neurons and in the ensemble response of the neural circuit, both in vivo (the whole animal/subject) and in vitro (e.g., cul...

High-precision differential scanning calorimetry (DSC) and circular dichroism (CD) have been employed to study the thermal unfolding of chitinase 40 (Chi40) from Streptomyces thermoviolaceus. Chi40 belongs to family 18 of glycosyl hydrolase superfamily bearing a catalytic domain with a "TIM barrel"-like fold, which exhibits deviations from the (beta/alpha)8 fold. The thermal unfolding is revers...

We demonstrate correlated rapid variability between the optical/UV and X-ray emission for the first time in a soft X-ray transient, GRO J1655–40: HST light curves show similar features to those seen by RXTE, but with mean delay of 10–20 s. We interpret the correlations as due to reprocessing of X-rays into optical and UV emission, with a delay due to finite light travel time, and thus perform e...

The prospects for imaging x rays at energies from 10 to 40 keV with grazing incidence optics are explored. The scientific rationale and existing laboratory measurements are reviewed. Measurements of reflectivity using possible mirror materials are described. Iridium-coated float glass gives an improved performance over gold by the factor predicted by theory but both had a lower absolute level. ...

Rubella virus and simina virus 40 (SV40) were isolated from a newborn child suffering from neurological and anatomical anomalies. The SV40 isolate was very similar to SV40 strain 777 by electron microscopic, biological, and immunological criteria.

The spectra of plasmas produced by focusing the output of a Q-switched ruby laser (output I J) on the rare-earth metals have been studied. From samarium (Z = 62) to ytterbium (Z = 70), strong quasi-uniform continua are emitted in the wavelength range 40-2000 A. Line emission from the target elements is absent over most of this wavelength region, particularly below about 600 A. The use of these ...