Sperm-like nano-devices may revolutionise drug delivery inside the body

London: A team of scientists, including an Indian-origin researcher, are working on remote-controlled nano-devices that look like sperm that may one day deliver drugs to where they are needed in the body.
Peer Fischer of The Rowland Institute at Harvard University has revealed that the nanopropellers will mimic the corkscrew motion of flagella, the structures some bacteria use to swim through water.
He and his colleague Ambarish Ghosh have revealed that their nanopropellers are made of glass.
The researchers further revealed that each of them has a spherical head 200 to 300 nanometres across and a corkscrew-shaped tail 1 to 2 micrometres long - less than one-tenth the length of a human sperm.
Ghosh and Fischer covered a silicon wafer with glass beads to make these propellers, before depositing a vapour of silicon dioxide onto them.
While doing so they spun the wafer, causing the silicon dioxide to form corkscrew-shaped tails on each bead. Finally, once the silicon dioxide had solidified they covered one side of the nanopropellers with cobalt.
Ghosh and Fischer say that the nanopropellers can be steered precisely.
"We control the coils that give rise to the magnetic field. By changing the magnetic field in three dimensions we can steer and propel the propellers," New Scientist quoted Fischer as saying.
The team have shown that a nanopropeller can push a silica bead over 1000 times larger than itself. They believe that their work may revolutionise drug delivery to specific areas of the body via the bloodstream, or even to conduct surgery.

'Smart turbine blades' to improve wind power

Washington: In a new research, scientists have developed a technique that uses sensors and computational software to constantly monitor forces exerted

on wind turbine blades, a step towardimproving efficiency by adjusting for rapidly changing wind conditions.
The research, by engineers at Purdue University and Sandia National Laboratories, is part of an effort to develop a smarter wind turbine structure
"The ultimate goal is to feed information from sensors into an active control system that precisely adjusts components to optimize efficiency," said Purdue doctoral student Jonathan White, who is leading the research with Douglas Adams, a professor of mechanical engineering

and director of Purdue's Center for Systems Integrity.
The system also could help improve wind turbine reliability by providing critical real-time information to the control system to prevent catastrophic wind turbine damage from high winds.
The engineers embedded sensors called uniaxial and triaxial accelerometers inside a wind turbine blade as the blade was being built.
The blade is now being tested on a research wind turbine at the US Department of Agriculture's Agriculture Research Service laboratory in Bushland, Texas.
Such sensors could be instrumental in future turbine blades that have "control surfaces" and simple flaps like those on an airplane's wings to change the aerodynamic characteristics of the blades for better control.
Because these flaps would be changed in real time to respond to changing winds, constant sensor data would be critical.
Research findings show that using a trio of sensors and "estimator model" software developed by White accurately reveals how much force is being exerted on the blades.
"You want to be able to control the generator or the pitch of the blades to optimize energy capture by reducing forces on the components in the wind turbine during excessively high winds and increase the loads during low winds. In addition to improving efficiency, this should help improve reliability," said Adams.
"We envision smart systems being a potentially huge step forward for turbines," said Sandia's Rumsey.
"There is still a lot of work to be done, but we believe the payoff will be great. Our goal is to provide the electric utility industry with a reliable and efficient product. We are laying the groundwork for the wind turbine of the future," he added.
Purdue and Sandia have applied for a provisional patent on the technique.