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In a world of rapidly accelerating change, from iPads to eBooks to genetic mapping to MagLev trains, we can't help but wonder if technology is our servant or our master, and whether it is taking us in a healthy direction as a society.* What forces drive the steady march of innovation?* How can we build environments in our schools, our businesses, and in our private lives that encourage the creation of new ideas--ideas that build on the new technology platforms in socially responsible ways?Kevin Kelly and Steven Johnson look at where technology is taking us. One of the co-founders of Wired Magazine, Kelly's new book, What Technology Wants, makes the argument that technology as a whole is not a jumble of wires and metal but a living, evolving organism that has its own unconscious needs and tendencies. Johnson's new book, Where Good Ideas Come From, explains why certain spaces, from 18th-century coffeehouses to the World Wide Web, have an uncanny talent for encouraging innovative thinking.

Engineers at Stevens Institute of Technology have developed a technique to optically modulate the frequency of a laser beam and create a signal that is disrupted significantly less by environmental factors, says Dr. Rainer Martini. The research provides for enhanced optical communications, allowing mobile units not tied to fiber optic cable to communicate in the range of 100 GHz and beyond, the equivalent of 100 gigabytes of data per second. Eventually, the team hopes to extend the reach into the terahertz spectrum. The frequency or amplitude modulation of middle infrared quantum cascade lasers has been limited by electronics, which are barely capable of accepting frequencies of up to 10 GHz by switching a signal on and off.  Marini and his team have developed a method to optically induce fast amplitude modulation in a quantum cascade laser to control the laser's intensity. Their amplitude modulation system employed a second laser to modulate the amplitude of the middle infrared laser, using light to control light. The current detector is only capable of detecting frequencies up to 10 GHz, but Dr. Martini is confident that a new detector will make the system capable of much higher frequencies. With an optical system that is stable enough, satellites may one day convert to laser technology, resulting in a more mobile military and super-sensitive scanners, as well as faster Internet for the masses, says Martini. Ref.: "Optically induced fast wavelength modulation in a quantum cascade laser," Applied Physics Letters, July 7, 2010.

Researchers from Purdue University and colleagues are developing new technologies that combine a laser and electric fields to manipulate fluids and tiny particles such as bacteria, viruses, and DNA molecules for a wide range of potential applications, including medical diagnostics, testing food and water, crime-scene forensics, and pharmaceutical manufacturing.. This "hybrid optoelectric manipulation in microfluidics" technology could allow for innovative sensors and analytical devices for "lab-on-a-chip" applications, or miniature instruments that perform measurements normally requiring large laboratory equipment, the researchers said. The technology works by first using a red laser to position a droplet on a platform specially fabricated at Purdue. Next, a highly focused infrared laser is used to heat the droplets, and then electric fields cause the heated liquid to circulate in a "microfluidic vortex." This vortex is used to isolate specific types of particles in the circulating liquid, like a micro centrifuge. Particle concentrations replicate the size, location and shape of the infrared laser pattern. The technology can also be used in nanomanufacturing because it shows promise for the assembly of suspended particles (colloids), the researchers said. Ref.: Steven T. Wereley, et al., Hybrid opto-electric manipulation in microfluidics-opportunities and challenges, Lab on a Chip, 2011; 11 (13): 2135 [DOI: 10.1039/C1LC20208A]