Researchers have made a small boat that doesn't require oars or pedals to move forward but relies on the energy of the water surface itself.

The mechanism is inspired by the larvae of the beetle Pyrrhalta. A pyrrhalta larva floating on the water propels itself forward by bending its back, releasing surface tension on its head and tail, and creating a capillary thrust that pulls it forward. The two-centimeter-long boat, designed by researchers at the University of Pittsburgh and presented at the MEMS 2009 conference in Sorrento, Italy, this week, uses a low-energy electrode to change the surface tension at its tail end to create propulsion, and another electrode at the front to act as a rudder. It could be powered by a solar panel and developed into a low-maintenance water-quality monitoring device. The video below shows the boat in action; the second half shows the rudder capability.

A fluorescent micrograph of viable cells captured using a biochemical trigger to actuate the gripper. Courtesy of the National Academy of Sciences (PNAS).

A remote-controlled microgripping "hand" could help give surgeons greater control during minimally invasive surgeries such as biopsies. In a story last August, frequent TR freelancer Prachi Patel-Predd described how the tiny hand works. Now the Johns Hopkins University researchers developing the microgripper have published a paper in the Proceedings of the National Academy of Sciences updating their work and including some neat video footage (see below). In the clip, the researchers use magnets to navigate a gripper through a coiled tube and to guide it toward a dyed bead and a cell mass. The grippers can close like a fist around an object in response to biochemical cues; in the future, they could even respond to biomolecules characteristic of cancer cells. The microhand in these videos grips the blue bead and the cell mass in response to an increase in temperature.

Eli Peli, a researcher at the Schepens Eye Research Institute in Boston, is developing software that can enhance the quality of a TV image for people with visual impairments such as macular degeneration--a disease that makes images on the screen seem blurred and distorted.

Peli's algorithms increase the contrast of a picture over spatial frequencies that are easier for a visually impaired person to see. In his lab a remote control can be used to adjust the contrast on a 32 inch television screen connected to a PC, creating a specially-enhanced picture.

"It's simple," Peli says, showing me CNN, the movie Shrek and a basketball game all in split-screen mode. In each clip he points out the difference in resolution, even for a person with normal eyesight. In the image on the right, details like grass, flowers and a person's facial features are much clearer than in the one on the left. Peli, who is also a professor of ophthalmology at Harvard Medical School, expects a grant from Analog Devices in the new year. This company has been testing his software and Peli says it is eager to build it into its hardware. He explains his work and demonstrates the system in the video below.

Video by Brittany Sauser