Nanodevice breaks 1-GHz barrier

Nanoscientists have achieved a milestone in their burgeoning field by creating a device that vibrates a billion times per second, or at one gigahertz (1 GHz). The accomplishment further increases the likelihood that tiny mechanical devices working at the quantum level can someday supplement electronic devices for new products.

Shear force of blood flow is crucial to embryonic heart development

A team of California researchers has imaged the blood flow inside the heart of a growing embryonic zebrafish. The results demonstrate for the first time that the very action of high-velocity blood flowing over cardiac tissue is an important factor in the proper development of the heart–a result that could have profound implications for future surgical techniques and even for genetic engineering.

Scientists Develop New Gene Therapy Approach

Researchers have developed a new gene therapy approach that prevents the AIDS virus from entering human cells. The technique offers a potential way to treat HIV patients and could apply to any disease caused by a gene malfunction, including cancer. The research team created a new application for a genetic technology called small interfering RNA (siRNA). The synthetically designed siRNAs act as a catalyst to reduce the expression of specific genes and slow the progression of disease.

Methane Clouds Discovered at the South Pole of Titan

Teams of astronomers at the California Institute of Technology and the University of California at Berkeley have discovered methane clouds near the south pole of Titan. Titan is Saturn’s largest moon, larger than the planet Mercury, and is the only moon in our solar system with a thick atmosphere. Like Earth’s atmosphere, the atmosphere on Titan is mostly nitrogen. Unlike Earth, Titan is inhospitable to life due to the lack of atmospheric oxygen and its extremely cold surface temperatures (-183 C; -297 F). Along with nitrogen, Titan’s atmosphere contains a significant amount of methane. Earlier spectroscopic observations had hinted at the existence of clouds on Titan, but gave no clue as to their location.

New Theory Accounts for Existence of Binaries in Kuiper Belt

In the last few years, researchers have discovered more than 500 objects in the Kuiper belt, a gigantic outer ring in the outskirts of the solar system, beyond the orbit of Neptune. Of these, seven so far have turned out to be binaries–two objects that orbit each other. The surprise is that these binaries all seem to be pairs of widely separated objects of similar size. This is surprising because more familiar pairings, such as the Earth/moon system, tend to be unequal in size and/or rather close together. To account for these oddities, scientists from the California Institute of Technology have devised a theory of Kuiper belt binary formation.

NASA Awards Caltech Five-Year, $8 billion JPL Contract

NASA has awarded the California Institute of Technology a new five-year contract to manage the Jet Propulsion Laboratory. It is estimated the contract will cover more than $8 billion worth of work. The contract extends for five years the JPL agreement between Caltech and NASA for management of JPL beyond its current expiration date of Sept. 30, 2003. The NASA contract includes a new provision that, based on performance reviews, may extend the contract period of performance for up to an additional five years.

Choreography, not molecular prepattern, creates vertebrate building blocks

In a study that combines state-of-the-art biological imaging with gene expression analysis, scientists at the California Institute of Technology have uncovered a fundamental insight into the way embryonic cells and tissue move about to form key structures along the vertebrate axis. The study, which could lead to a better understanding of human development, takes advantage of the accessibility of chick embryos to embryonic manipulation. The study enters on segments known as somites, which form along either side of the future spinal cord of an embryo. Somites give rise to mature structures such as ribs, individual vertebrae, and even skin. The key role of somite segmentation in the patterning of the nervous system and the vertebral column has been long known. But the question of precisely how an individual somite buds off from a block of tissue in a pattern that is repeated all along the animal’s torso, from head to tail, is poorly understood.

Chaos Seen in Movement of Ring-Herding Moons of Saturn

Chaos can explain the seemingly random behavior of two moons of Saturn, JPL researchers say. The moons — Pandora and Prometheus — are more than 100,000 miles off course of where they would be if their orbits followed conventional physics. “With chaotic interactions, a barely perceptible difference in starting conditions can make such a great difference in later positions that the movements are not fully predictable over time. The two moons give each other a gravitational kick each time Pandora passes inside Prometheus, about every 28 days. Because neither’s orbit is quite circular, the distance between them on those occasions — hence the strength of the kick — varies.”