Bacteria have evolved different systems for secreting proteins. One, called a type VI secretion system, is found in about a quarter of all bacteria with two membranes. Despite being common, researchers have not understood how it works. Now a team, co-led by researchers at Caltech, has figured out the structure of the type VI secretion system apparatus and proposed how it might work—by shooting spring-loaded poison molecular daggers.
Three new faculty members in the Division of Engineering and Applied Science (EAS) have big ideas about really small things. Assistant professors Hyuck Choo, Dennis Kochmann, and Austin Minnich focus on quite different challenges, but they all home in on the nanoscale, where they manipulate, model, and measure structures and phenomena at the level of individual atoms.
A team of undergrads recently received accolades for their research at an international competition in Boston. Their studies, which earned them a gold award at the 2011 International Bio-Molecular Design Competition, started out as a summer undergrad research fellowship (SURF) project. The group also received a third place ranking in the "best wiki" prize category, based on a series of web pages that explained their project, "DeoxyriboNucleicAwesome."
For the first time, researchers at Caltech, in collaboration with a team from the University of Vienna, have managed to cool a miniature mechanical object to its lowest possible energy state using laser light. The achievement paves the way for the development of exquisitely sensitive detectors as well as for quantum experiments that scientists have long dreamed of conducting.
In the last couple of years, researchers have observed that water spontaneously flows into extremely small tubes of graphite or graphene, called carbon nanotubes. However, no one has managed to explain why. Now, using a novel method to calculate the dynamics of water molecules, Caltech researchers believe they have solved the mystery. It turns out that entropy, a measurement of disorder, has been the missing key.
Stretching for thousands of miles beneath oceans, optical fibers now connect every continent except for Antarctica. But although optical fibers are increasingly replacing copper wires, carrying information via photons instead of electrons, today's computer technology still relies on electronic chips. Now, researchers led by engineers at the Caltech are paving the way for the next generation of computer-chip technology: photonic chips.
At the forefront of nanotechnology, researchers design miniature machines to do big jobs, from treating diseases to harnessing sunlight for energy. But as they push the limits of this technology, devices are becoming so small and sensitive that the behavior of individual atoms starts to get in the way. Now Caltech researchers have, for the first time, measured and characterized these atomic fluctuations—which cause statistical noise—in a nanoscale device.
Caltech scientists have conducted experiments confirming which of three possible mechanisms is responsible for the spontaneous formation of 3-D pillar arrays in nanofilms. These protrusions appear suddenly when the surface of a molten nanofilm is exposed to an extreme temperature gradient and self-organize into hexagonal, lamellar, square, or spiral patterns.