How nanocrystals lost their blink

How HIV-1 lost control

C ells with a defective spindle get delayed—stuck in a mitotic checkpoint—but eventually escape mitosis. In vertebrate cells, say Daniela Brito and Conly Rieder (Wadsworth Center, New York State Department of Health, Albany, NY), that escape is a gradual limp rather than a sudden exit. The temporary stalling of the cell cycle in a checkpoint gives the cell time to repair damage before continuin...

Have Americans Lost Their Minds?

How the snake lost its legs

mystery of how the snake lost its legs might make a good 'Just so' story but it's also a tantalizing developmental question. Snakes have hundreds of similar vertebrae, as shown by the stained skeleton of a python embryo, Antaresia maculosa, (24 days after egg-laying) at top left. Snakes have no forelimbs but pythons have a pair of hindlimb rudiments (removed in picture at top right) at the junc...

Simultaneous ram pressure and tidal stripping; how dwarf spheroidals lost their gas

We perform high-resolution N-Body+SPH simulations of gas-rich dwarf galaxy satellites orbiting within a Milky Way-sized halo and study for the first time the combined effects of tides and ram pressure. The structure of the galaxy models and the orbital configurations are chosen in accordance to those expected in a ΛCDM Universe. While tidal stirring of disky dwarfs produces objects whose stella...

Negative attentional set in the attentional blink: control is not lost.

The attentional blink (AB) refers to the finding that performance on the second of two targets (T1 and T2) in a rapidly presented stimulus stream is impaired when the targets are presented within 200-500 ms. This study investigates whether a negative attentional set, a form of top-down control, has an additional detrimental effect, and whether its influence is modulated by task demands. A negat...