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Professor Keith Mason, Chief Executive of the Science and Technology Facilities Council which funds UK space science said “BepiColombo will make the most detailed study of Mercury ever, revealing the secrets of the planet closest to the Sun – what it is formed of, how the Sun affects it and what we can learn about the other planets by comparison. It is technically challenging to send a probe to Mercury due to the extreme heat conditions, high levels of radiation and the strong gravitational pull of the Sun. A mission of this complexity reveals the ingenuity of our scientists and engineers.”

BepiColombo consists of two spacecraft. One spacecraft, ESA’s Mercury Planetary Orbiter (MPO), will carry 11 instruments to study the surface and internal composition of the planet with unprecedented accuracy, using different wavelengths and investigation techniques.

The second spacecraft, JAXA’s Mercury Magnetospheric Orbiter (MMO), will carry five instruments to study the planet’s magnetosphere, the region of space around the planet that is dominated by its magnetic field.

Professor George Fraser of the University of Leicester Space Research Centre is leading a research team from five countries to build the Mercury Imaging X-ray Spectrometer (MIXS) which will fly on the MPO craft. He said “MIXS will look at the x-rays coming from the planet Mercury to study the composition of the surface, helping us to test models of the planet’s formation. X-ray remote sensing has told us a great deal about the Moon and the asteroids, but MIXS will be the first true x-ray imaging telescope to be used in planetary science.”

Dr David Rothery of the Open University, who is the UK Lead Scientist for MIXS and Co-Chairman of ESA’s Mercury Surface and Composition Working Group, said: “The preliminary close-up images from NASA’s MESSENGER flyby of Mercury this week offer tantalising indications of a complex history of lava flows partly burying the planet’s more ancient primitive crust. The high spatial resolution achievable by MIXS will be vital in order to distinguish the compositions of these two very different types of crust, which is essential if we are to unravel the mysteries of Mercury’s origin and evolution.”

Magna Parva, a specialist firm from Loughborough are developing, the mechanical structure for the MIXS telescope with the University of Leicester Space Research Centre. The MIXS Optics structure is an extremely challenging mechanical engineering project that involves working alongside Prof. Fraser and his team to ensure that the science objectives of the MIXS instrument are met. The decision to involve a small, relatively unknown, flexible company in the MIXS project has brought an innovative approach to instrument design and may provide a model for UK space science projects in the future.

A vital sister instrument to MIXS is the Solar Intensity X-ray Spectrometer (SIXS), led from Finland, which will measure the x-rays and particles from the Sun that trigger the fluorescence on Mercury’s surface.

Engineers at STFC’s Rutherford Appleton Laboratory are working on integrated circuits for reading out signals from the detectors of the SIXS instrument. These have been manufactured and testing will begin shortly.

On behalf of ESA, the prime contractor Astrium will lead a network of subcontractors to design and build ESA’s MPO spacecraft and the so-called Mercury Transfer Module - that is the module to carry the MPO-MMO composite spacecraft to its destination.

Astrium in the UK is responsible for the structure of the entire spacecraft including the launch vehicle adapter, the complex mission analysis that will require numerous swing-bys of the Earth, the moon, and Venus in its six year flight plan, and also the two chemical propulsion systems and the ion propulsion system.

An additional difficulty is that reaching Mercury and then entering into orbit requires a large amount of energy to brake against the Sun’s gravity. To achieve this, the cruise and the orbit insertion phases will primarily rely on solar-electric propulsion (as tested on ESA’s Smart-1 mission to the Moon), complemented by several planetary gravity-assist manoeuvres and conventional (chemical) propulsion.

“Mercury is the planet closest the Sun, making it hard to get to and so it is a technical challenge by anyone’s measure,” said Prof. David Southwood, ESA’s Director of Science. “However Mercury has also regularly confounded planetary scientists with its exceptional properties and that makes it a grand scientific challenge.”

Adapted from materials provided by Science and Technology Facilities Council.

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The OWNFOR system is deployed at sea and drifts while videotaping the movement of a larva placed within a clear, circular arena. It will also be possible to change their immediate environment and manipulate orientation cues, such as acoustic, chemical, or magnetic fields that larvae may use to navigate. This new system will be equipped with an infrared camera that can verify the larvae’s orientation at night.

Through a research grant from The Hermon Slade Foundation and a fellowship from the Australian Museum, she will be putting her new larval monitoring system to the test in early 2008. Paris and colleagues are interested in gathering data on the successful identification of larval abilities to orientate as they mature.

“Typical research on larvae is assessed in laboratory experiments or in studies done in situ with the naked eye, but it does not provide information on whether or not larvae use cues to find a home, when in their life history they use them, or how far from the reef they can sense the cues. We’re hoping to find out how the larvae behaviorally interact with the blue-water environment minimizing human intervention,” said Paris. “The success of this new device in recording true orientation in fish larvae opens new possibilities for research in the field of larval ecology.”

Working at the Lizard Island Research Station, a satellite-facility of the Australian Museum on the Great Barrier Reef, Paris will directly compare her research methods with those of Lizard Island researcher, Dr. J.M. Leis, who published his results diving and following larval fish. Researchers hope that OWNFOR will provide minimal interference in the natural migration of organisms, helping to understanding just what influences these organisms to settle on a final reef home after days or weeks in a relatively featureless open ocean landscape.

“The larval phase is often the main opportunity in benthic organisms to colonize new habitats, but how far from home are these new habitats? They can range from tens of kilometers away to the natal reef (reef of origin). Ideally, we’ll discover crucial inputs for a new generation of biophysical larval dispersal models vital to achieving a better understanding of larval connectivity in marine systems,” said Paris. “The implications will have global impacts on the effective management of fisheries, conservation of marine biodiversity, including design of marine reserves, and helping to predict the effects of climate change on marine systems.”

Paris earned her master’s degree in biology and living resources from the Rosenstiel School, and her Ph.D. in coastal oceanography from SUNY Stony Brook’s Marine Sciences Research Center. Her current research is also funded by the National Science Foundation’s division of Ocean Science (OCE).

Adapted from materials provided by University of Miami Rosenstiel School of Marine & Atmospheric Science.

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The car-sized MESSENGER spacecraft is carrying seven instruments — a camera, a magnetometer, an altimeter and four spectrometers. The Mercury Atmospheric and Surface Composition Spectrometer, or MASCS, built by CU-Boulder’s Laboratory for Atmospheric and Space Physics, was miniaturized to weigh less than seven pounds.

During the flyby, the probe’s instruments will gather data essential to planning the MESSENGER mission’s orbital phase. MESSENGER’s scientific instruments will begin to address the mission goals of:

* mapping the elemental and mineralogical composition of Mercury’s surface;
* imaging globally the surface at a resolution of hundreds of meters or better;
* determining the structure of the planet’s magnetic field;
* measuring the planet’s gravitational field structure; and
* characterizing exospheric neutral particles and magnetospheric ions and electrons.

The instrument will make measurements of Mercury’s surface and tenuous atmosphere, said LASP Senior Research Associate William McClintock, a MESSENGER co-investigator who led the MASCS instrument development team. MASCS breaks up light like a prism, and since each element and compound in the universe has a unique spectral “signature,” scientists can determine the distribution and abundance of various minerals and gases on the planet’s surface and its atmosphere.

“Believe it or not, scientists have only a vague idea today about the composition of Mercury’s surface,” said McClintock. “The instrument will make ultraviolet, visible and near infrared observations of the surface of Mercury, which together should tell us a lot more about the planet’s composition, formation and evolution.”

MESSENGER is slated to zip by Mercury at about 11:25 a.m. MST on Jan. 14 and take data and images for about 90 minutes, said LASP’s Mark Lankton, program manager for MASCS. The data will be sent via NASA’s Deep Space Network to the Applied Physics Laboratory at Johns Hopkins University — which is managing the mission for NASA — where mission scientists, including researchers and students at LASP’s Space Technology Building at the CU Research Park, will access it electronically, he said.

The circuitous, 4.9 billion-mile-journey to Mercury requires more than seven years and 13 loops around the sun to guide it closer to Mercury’s orbit. The craft is equipped with a large sunshade and heat-resistant ceramic fabric to protect it from the sun. More than half of the weight of the 1.2-ton spacecraft consists of propellant and helium.

“The LASP team is really spun up for this flyby,” said Lankton. “It’s very exciting, because this is the beginning of the science phase of the MESSENGER mission. It’s a chance for us to make observations that have never been made before.”

MASCS will scan Mercury’s thin atmosphere — known as the exosphere — to determine its composition, and the spacecraft will fly through a comet-shaped cloud of sodium enveloping the planet during the flyby, said McClintock. “We will fly it right down the cloud’s tail,” he said. “Understanding how the cloud is replenished with sodium is one of the many pieces of this giant puzzle at Mercury we hope to solve.”

LASP Director Daniel Baker, also a co-investigator on the MESSENGER mission, will be studying Mercury’s magnetic field and its interaction with the solar wind, including violent “sub-storms” that occur in the planet’s vicinity. The strong magnetic field on Mercury indicates it most likely has a liquid or molten core like that on Earth, Baker said.

Mercury is about two-thirds of the way nearer to the sun than Earth and is bombarded with 10 times the solar radiation, said Baker. Sandwiched by the sun and Mercury — which has daytime temperatures of about 800 degrees Fahrenheit — the MESSENGER spacecraft will “essentially be on a huge rotisserie,” he said.

LASP’s vast experience in space during the last several decades should serve the team well. “We are the only space lab in the world to design and build instruments that are either on the way to or have visited every planet in the solar system,” Baker said. “Because of our successes, I view our scientists, engineers and support staff and students like a Super Bowl team. We have star players at every position.”

Dozens of undergraduates and graduate students will be involved in analyzing data as information and images begin pouring back to Earth from MESSENGER, dubbed “the little spacecraft that could” by LASP scientists. “This mission is going to be a field day for students, not only at CU-Boulder, but for students all over the world,” said Baker.

Adapted from materials provided by University of Colorado at Boulder.

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Artist depiction of the white dwarf in the AE Aquarii system Image right: The white dwarf in the AE Aquarii system is the first star of its type known to give off pulsar-like pulsations that are powered by its rotation and particle acceleration. (Credit: Casey Reed)

New observations from Suzaku, a joint Japanese Aerospace Exploration Agency (JAXA) and NASA X-ray observatory, have challenged scientists’ conventional understanding of white dwarfs. Observers had believed white dwarfs were inert stellar corpses that slowly cool and fade away, but the new data tell a completely different story.

At least one white dwarf, known as AE Aquarii, emits pulses of high-energy (hard) X-rays as it whirls around on its axis. “We’re seeing behavior like the pulsar in the Crab Nebula, but we’re seeing it in a white dwarf,” says Koji Mukai of NASA Goddard Space Flight Center in Greenbelt, Md. The Crab Nebula is the shattered remnant of a massive star that ended its life in a supernova explosion. “This is the first time such pulsar-like behavior has ever been observed in a white dwarf.” Mukai is co-author of a paper presented at a Suzaku science conference in San Diego, Calif., in December.

White dwarfs and pulsars represent distinct classes of compact objects that are born in the wake of stellar death. A white dwarf forms when a star similar in mass to our sun runs out of nuclear fuel. As the outer layers puff off into space, the core gravitationally contracts into a sphere about the size of Earth, but with roughly the mass of our sun. The white dwarf starts off scorching hot from the star’s residual heat. But with nothing to sustain nuclear reactions, it slowly cools over billions of years, eventually fading to near invisibility as a black dwarf.

A pulsar is a type of neutron star, a collapsed core of an extremely massive star that exploded in a supernova. Whereas white dwarfs have incredibly high densities by earthly standards, neutron stars are even denser, cramming roughly 1.3 solar masses into a city-sized sphere. Pulsars give off radio and X-ray pulsations in lighthouse-like beams.

The discovery team, led by Yukikatsu Terada of the Institute of Physical and Chemical Research (RIKEN) in Wako, Japan, was not expecting to find a white dwarf mimicking a pulsar. Instead, the astronomers were hoping to find out if white dwarfs could accelerate charged subatomic particles to near-light speed, meaning they could be responsible for many of the cosmic rays that zip through our galaxy and occasionally strike Earth.

Some white dwarfs, including AE Aquarii, spin very rapidly and have magnetic fields millions of times stronger than Earth’s. These characteristics give them the energy to generate cosmic rays.

To find out if this is happening, Terada and his colleagues targeted AE Aquarii with Suzaku in October 2005 and October 2006. The white dwarf resides in a binary system with a normal companion star. Gas from the star spirals toward the white dwarf and heats up, giving off a glow of low-energy (soft) X-rays. But Suzaku also detected sharp pulses of hard X-rays. After analyzing the data, the team realized that the hard X-ray pulses match the white dwarf’s spin period of once every 33 seconds.

The hard X-ray pulsations are very similar to those of the pulsar in the center of the Crab Nebula. In both objects, the pulses appear to be radiated like a lighthouse beam, and a rotating magnetic field is thought to be controlling the beam. Astronomers think that the extremely powerful magnetic fields are trapping charged particles and then flinging them outward at near-light speed. When the particles interact with the magnetic field, they radiate X-rays.

“AE Aquarii seems to be a white dwarf equivalent of a pulsar,” says Terada. “Since pulsars are known to be sources of cosmic rays, this means that white dwarfs should be quiet but numerous particle accelerators, contributing many of the low-energy cosmic rays in our galaxy.”

Launched in 2005, Suzaku is the fifth in a series of Japanese satellites devoted to studying celestial X-ray sources. Managed by JAXA, this mission is a collaborative effort between Japanese universities and institutions and Goddard.

Adapted from materials provided by NASA/Goddard Space Flight Center.

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“It’s thought that RNA, or a molecule like it, may have been among the first molecules of life, both carrying genetic code that can be transmitted from generation to generation and folding into structures so these molecules could work inside cells,” said Purdue structural biologist Barbara Golden. “At some point, RNA evolved and became capable of making proteins. At that point, proteins started taking over roles that RNA played previously - acting as catalysts and building structures in cells.”

In order to show this and learn more about the evolution from RNA to more complex life forms, Lambowitz and Paul Paukstelis, lead author and a research scientist at the Texas institute, needed to be able to see how the fungus’ protein worked. That’s where Golden’s team joined the effort and crystallized the molecule at Purdue’s macromolecular crystallization facility.

“Obviously, we can’t see the process of moving from RNA to RNA and proteins and then to DNA, without a time machine,” Golden said. “But by using this fungus protein, we can see this process occurring in modern life.”

Looking at the crystal, the scientists saw two things, Golden said. One was that this protein uses two completely different molecular surfaces to perform its two roles. The second is that the protein seems to perform the same job that RNA performed in other simple organisms.

“The crystal structure provides a snapshot of how, during evolution, protein molecules came to assist RNA molecules in their biological functions and ultimately assumed roles previously played by RNA,” Golden said.

Before the crystallization, Lambowitz, Paukstelis and their research team at The University of Texas at Austin were involved in a long-term project to study the function of the basic cellular workhorse protein and other evolutionary fossils from the fungus. In earlier work, the scientists studied a different protein that showed how biochemical processes could progress from a world with RNA and protein to DNA.

The protein, as found in the fungus, had adapted to take over some of the RNA molecule’s chemical reaction jobs inside cells. The protein stabilizes the RNA molecule - called an intron - so that the RNA can cut out non-functional genetic material and splice together the ends of a functional gene, Paukstelis said.

“The RNA molecule in our study is capable of performing a specific chemical reaction on itself, but it requires a protein for this reaction to take place efficiently,” he said.

This basic scientific information eventually could lead to clinical applications.

“This work has potential applications in the development of antifungal drugs to battle potentially deadly pathogens; that’s one of the next steps,” Lambowitz said. “Another is to produce more detailed structures so that we can understand the ancient chemical reactions.”

Golden and Lambowitz are senior authors of the report. Golden is a member of the Markey Center for Structural Biology and Purdue Cancer Center. The Markey Center will be housed in the Hockmeyer Hall of Structural Biology when it’s completed on the West Lafayette campus.

Other researchers involved in this study along with Paukstelis were Jui-Hui Chen, a Purdue biochemistry doctoral student, and Elaine Chase, a Purdue biochemistry research technician.

Results of the study were published in the journal Nature January 3.

Adapted from materials provided by Purdue University.

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Scan of placoderm eye casing. The arrangement of muscles and nerves supporting the eyeball in placoderms provides evidence of an “intermediate stage” between the evolution of jawless and jawed vertebrates. (Credit: Image courtesy of Australian National University)

Ancient armoured fish fossils from Australia present some of the first definite fossil evidence of a forerunner to the human eye, a scientist from The Australian National University says.

Dr Gavin Young from the Department of Earth and Marine Sciences at ANU has analysed fossilised remains of 400-million-year-old Devonian placoderms – jawed ancestors of modern fish whose bodies were protected by thick bony armour.“The ancient limestone reefs exposed around Lake Burrinjuck in New South Wales have produced exceptionally well preserved placoderm specimens with the braincase intact,” Dr Young said.

The palaeobiologist discovered that unlike all living vertebrate animals – which includes everything from the jawless lamprey fish to humans – placoderms had a different arrangement of muscles and nerves supporting the eyeball – evidence of an “intermediate stage” between the evolution of jawless and jawed vertebrates.

“The vertebrate eye is the best example of structural perfection – as used by proponents of intelligent design to claim that something so complex couldn’t possibly have evolved,” Dr Young said.

“Part of the trouble in tracing the evolution of the eye is that soft tissues don’t tend to fossilise. But the eye cavities in the braincase of these 400 million-year-old fossil fish were lined with a delicate layer of very thin bone. All the details of the nerve canals and muscle insertions inside the eye socket are preserved – the first definite fossil evidence demonstrating an intermediate stage in the evolution of our most complex sensory organ.

“These extinct placoderms had the eyeball still connected to the braincase by cartilage, as in modern sharks, and a primitive eye muscle arrangement as in living jawless fish.” Dr Young said that this anatomical arrangement is different from all modern vertebrates, in which there is a consistent pattern of tiny muscles for rotating each eyeball.

The placoderm fossils were analysed using computer X-ray tomography at ANU, a scanning technique that creates a three-dimensional image of complex organic structures. “What this research shows is that 400 million years ago there was already a complex eye, and one that was an intermediate form between jawless and jawed vertebrates,” Dr Young says. “This means that we’re able to add one more piece to the puzzle of how the human eye came to be.”

These findings are published in a recent edition of Biology Letters, a journal of the Royal Society, London.

Adapted from materials provided by Australian National University.

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Dr Paula Chadwick of the University of Durham said “This picture really is a big step forward for gamma-ray astronomy and the supernova remnant is a fascinating object. If you had gamma-ray eyes and were in the Southern Hemisphere, you could see a large, brightly glowing ring in the sky every night.”

Professor Ian Halliday, CEO of PPARC which funds UK participation in H.E.S.S. said “These results provide the first unequivocal proof that supernovae are capable of producing large quantities of galactic cosmic rays - something we have long suspected, but never been able to confirm.”

Gamma rays are the most penetrating form of radiation we know, around a billion times more energetic than the X-rays produced by a hospital X-ray machine. This makes it very difficult to use them to create an image - they just pass straight through any surface which we might use to reflect them, for instance. However, luckily for life on Earth, gamma rays from objects in outer space are stopped by the atmosphere; when this happens, a faint flash of blue light is produced, lasting for a few billionths of a second. The astronomers used images of these flashes of light, called Cherenkov radiation, to make a gamma ray ‘image’ for the first time.

Adapted from materials provided by Particle Physics & Astronomy Research Council.

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These cosmic powerhouses pour out vast amounts of energy, and they accelerate particles to almost the speed of light. But very little is known about these sources because they were discovered only recently. “Understanding these objects is one of the most intriguing problems in astrophysics,” says Takayasu Anada of the Institute for Space and Astronautical Science in Kanagawa, Japan. Anada is lead author of a paper presented last week at a Suzaku science conference in San Diego, Calif.

These mysterious objects have been discovered in just the last few years by an array of four European-built telescopes named the High Energy Stereoscopic System (H.E.S.S.), located in the African nation of Namibia. H.E.S.S. indirectly detects very-high-energy gamma rays from outer space. These gamma rays are the highest-energy form of light ever detected from beyond Earth, so H.E.S.S. and other similar arrays have opened up a new branch of astronomy.

The gamma rays themselves are absorbed by gases high up in Earth’s atmosphere. But as the gamma rays interact with air molecules, they produce subatomic particles that radiate a blue-colored light known as Cherenkov radiation. H.E.S.S. detects this blue light, whose intensity and direction reveals the energy and position of the gamma-ray source.

The H.E.S.S. observations were groundbreaking, but the array’s images aren’t sharp enough to reveal the exact location where particles are being accelerated or how the particles are being accelerated. To solve this problem, several teams aimed Suzaku in the direction of some of these H.E.S.S. sources. Any object capable of emitting high-energy gamma rays will also produce X-rays, and Suzaku is particularly sensitive to high-energy (hard) X-rays.

When Anada and his colleagues pointed Suzaku at a source known as HESS J1837-069 (the numerals express the object’s sky coordinates), the X-ray spectrum closely resembled X-ray spectra of pulsar wind nebulae — gaseous clouds that are sculpted by winds blown off by collapsed stars known as pulsars. Pulsar wind nebulae emit hard X-rays, and their X-ray output remains relatively constant over long timescales. “The origin of the gamma-ray emission from HESS J1837-069 remains unclear, but we suspect that this source is a pulsar wind nebula from the Suzaku observation,” says Anada.

NASA’s Chandra X-ray Observatory and the European Space Agency’s XMM-Newton X-ray Observatory have revealed that other H.E.S.S. sources are also pulsar wind nebulae. These combined gamma-ray and X-ray observations are revealing that pulsar wind nebulae are more common and more energetic than astronomers had expected.

Another group, led by Hironori Matsumoto of the University of Kyoto in Japan, targeted Suzaku on HESS J1614-518. This source belongs to a class of objects known as “dark particle accelerators” because their ultrahigh energies suggest they are accelerating particles to near-light speed, turning them into cosmic rays. But what are these objects, and what kinds of particles are being accelerated?

Although the nature of these objects remains a mystery, Suzaku’s observations do reveal the identity of the particles. When electrons are accelerated to high speeds, they spiral around magnetic field lines that permeate space, generating copious X-rays. But since protons are 2,000 times more massive than electrons, they emit few X-rays. Matsumoto and his colleagues reported at the conference that HESS J1614-518 is a very weak X-ray emitter. “This result strongly suggests that high-energy protons are being produced in this object,” says Matsumoto.

Suzaku also observed two other H.E.S.S. dark particle accelerators, but found no obvious X-ray counterparts at the H.E.S.S. positions. These sources must also be weak X-ray emitters, indicating they are accelerating mostly protons. As Matsumoto says, “Using the high sensitivity of the Suzaku satellite, we can find strong candidates for the origin of cosmic rays.”

Launched in 2005, Suzaku is the fifth in a series of Japanese satellites devoted to studying celestial X-ray sources. Managed by JAXA, this mission is a collaborative effort between Japanese universities and institutions and NASA Goddard.

Adapted from materials provided by NASA/Goddard Space Flight Center.

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Barry Dickson, director of the Research Institute of Molecular Pathology (IMP) in Austria, and his group are interested in the genetic basis of innate behaviour. They focus on the reproductive behaviour of the fruit fly Drosophila melanogaster. Two years ago, the team was able to identify the fruitless gene as a key regulator of mating behaviour.

For 20 years, scientists have been trying to identify another molecular switch which changes the behaviour of female insects after mating. It makes them lose interest in further sexual contact and start laying eggs. Mosquitoes, once fertilized, look out for a meal of blood and may transmit the malaria parasite along the way.

The trigger for the behavioral switch is a factor present in the seminal fluid of male insects. This sex peptide (SP), as it is called in Drosophila, has been known to scientists for quite a while. Nilay Yapici, a PhD student in Barry Dickson’s team, has now identified the receptor (SPR) responsible for the effect of SP and thus revealed the underlying molecular mechanism. She also showed that the gene for SPR is active in the reproductive organs as well as the brain of the flies.

To get this far, it took two years of painstaking work and a scientific tool which was developed over the past few years by the Dickson group. This “Drosophila RNAi Library” is a collection of 22,000 fly strains and has recently been made available to researchers worldwide. Due to this collection, it is now possible to switch off any chosen gene in the fly. By doing so, neurobiologists are able to identify genes that influence behaviour.

Nilay Yapici studied 22,000 female flies and observed how they behaved after mating. In 130 cases, she found flies which continued to mate and laid very few or no eggs. Further evaluation of these genes and subsequent experiments with cell cultures led to the identification of the long-sought receptor, SPR. By activating or disrupting SPR in specific neurons, the receptor could be localized in the central nervous system of the fly.

Apart from the benefit to basic research, the discovery might offer new approaches for controlling the reproductive or host-seeking behaviours of various agricultural pests and human disease carriers. The molecular mechanism has remained remarkably stable in the course of evolution and SPR-like receptors can be found in many insect species. Ms. Yapici thinks that “It might be possible to develop a substance that blocks the receptor SPR. This inhibitor would work as a kind of ‘birth control pill’: female insects would continue to mate but would not lay eggs.”

Adapted from materials provided by Research Institute of Molecular Pathology.

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The findings of Jianguo “Jack” Liu and Eunice Yu at Michigan State University are published in the Proceedings of the National Academy of Sciences.

“Not only the United States, but also other countries, including developing countries such as China and places with strict religious policies regarding divorce, are having more divorced households,” Liu said. “The consequent increases in consumption of water and energy and using more space are being seen everywhere.”

Liu and his research assistant Yu started with the obvious — that divorce rates across the globe are on the rise. Housing units, even if they now have few people in them, require resources to construct them and take up space. They require fuel to heat and cool. A refrigerator uses roughly the same amount of energy whether it belongs to a family of four or a family of two.

When they calculated the cost in terms of increased utilities and unused housing space per capita, they discovered that divorce tosses out economy of scale. Among the findings:

* In the United States alone in 2005, divorced households used 73 billion kilowatt-hours of electricity and 627 billion gallons of water that could have been saved had household size remained the same as that of married households. Thirty-eight million extra rooms were needed with associated costs for heating and lighting.
* In the United States and 11 other countries such as Brazil, Costa Rica, Ecuador, Greece, Mexico and South Africa between 1998 and 2002, if divorced households had combined to have the same average household size as married households, there could have been 7.4 million fewer households in these countries.
* The numbers of divorced households in these countries ranged from 40,000 in Costa Rica to almost 16 million in the United States around 2000.
* The number of rooms per person in divorced households was 33 percent to 95 percent greater than in married households.

To track what happens when divorced people returned to married life, the study compared married households with households that had weathered marriage, divorce and remarriage. The results: The environmental footprint shrunk back to that of consistently married households.

Liu, a University Distinguished Professor of fisheries and wildlife and Rachel Carson Chair in Ecological Sustainability at MSU’s Center for Systems Integration and Sustainability, has spent more than two decades integrating ecology with social sciences to understand the complex interrelationships between nature and humans and how those interactions affect the environment and biodiversity. Liu and Yu began to discuss this research project when Yu was a high school student.

This new work also acknowledges that divorce is not the only lifestyle trend changing family living structures — the demise of multigenerational households, people remaining single longer are examples.

“People’s first reaction to this research is surprise, and then it seems simple,” Liu said. “But a lot of things become simple after research is done. Our challenges were to connect the dots and quantify their relationships. People have been talking about how to protect the environment and combat climate change, but divorce is an overlooked factor that needs to be considered.”

The research, Liu said, shows that environmental policy is more complex than one single solution. Governments across the world may need to start factoring in divorce when examining environmental policy, Liu said.

“Solutions are beyond a single idea,” Liu said. “Consider the production of biofuel. Biofuel is made from plants, which also require water and space. We’re showing divorce has significant competition for that water and space. On the other hand, more divorce demands more energy. This creates a challenging dilemma and requires more creative solutions.”

The research was funded by the National Science Foundation, the National Institutes of Health and the Michigan Agricultural Experiment Station.

Adapted from materials provided by Michigan State University.

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A research team led by Jue Chen, an associate professor of biological sciences, obtained a snapshot of the tiny protein gate complex that opens and closes pathways through the protective cellular membrane. The gates, operated by small protein machines that push them open and closed, bring nutrients into the cell and flush out waste.

The Purdue-led team was the first to achieve an image of the middle step of the process, capturing the molecular interactions as material passes through the membrane.

“By understanding the mechanisms of this process, researchers may be able to design more effective treatments for diseases that involve this group of proteins, such as cancer and cystic fibrosis,” said Chen, who also is a member of Purdue’s structural biology group within the College of Science. “With this knowledge, researchers may be able to inhibit or activate this mechanism, depending on what is needed to counteract the disease. For instance, many cancer cells are resistant to drug treatments because the cells pump the drugs out through these channels before they can work.”

Amy Davidson, who collaborated on this work with Chen, said capturing an image of the intermediate stage is a giant step toward learning the complete process.

“If you look at only the before and after stages, you don’t really know all that goes on,” said Davidson, an associate professor of chemistry at Purdue. “The intermediate stage provides all of this information about how the process really works. It shows all of the main components of the system interacting, which had not been seen before. It is a snapshot of what happens halfway through the entry process and is a very clear picture of how things work.”

The research team used X-ray crystallography to obtain a picture of a special protein, called an ABC transporter protein, as it moved material through the cellular membrane. The work was published in last week’s issue of Nature.

In addition to Davidson, Chen’s research team includes postdoctoral research associates Michael Oldham and Dheeraj Khare from Purdue, and professor Florante Quiocho from Baylor College of Medicine. The team began this work in 2001.

ABC proteins are present in every living thing and have important biological functions. Scientists have identified 49 different ABC proteins in humans and have found that more than a dozen disease states are associated with malfunctions of these proteins, including macular dystrophy and problems in the regulation of cholesterol and insulin secretion.

Chen’s team isolated ABC proteins from an E. coli bacterium, which is the standard research subject for this field of work. The ABC proteins are structurally very similar to those in human cells, and most of the principles can be directly applied to humans, Chen said.

Membrane proteins are notoriously difficult to study, Chen said. While most proteins dissolve in water and can be easily crystallized and examined, membrane proteins dissolve only in fatty substances, making it hard to isolate them for study.

The collaboration between Chen and Davidson, a structural biologist and a biochemist, was the key to success in capturing the intermediate structure, Chen said.

Davidson identified a special mutant of the ABC protein that locks halfway through the process. The mutant trapped the protein complex in a stable form that allowed Chen to crystallize and visualize the structure.

“We have the common goal to learn how this family of proteins works, but we take different approaches,” Chen said. “It is important to communicate with scientists in other fields who can offer clues and tools to help reach your goal. We used genetic data and biochemical data to learn what we needed to crystallize and solve the structure.”

While structural biologists attempt to obtain images of a protein as it performs a process, biochemists use indirect methods to understand the nature of a protein and how it moves through different conformations.

“Collaboration allows us to marry visual structures to other techniques that let you see the motions,” Davidson said. “It all came together beautifully and matched the model we proposed in 2001 of what things should look like during this process. Through genetic and biochemical work we determined which proteins were important to this process, but we didn’t know exactly how they worked. The image of the structure answers these questions and clearly shows the specific interactions.”

Next, the team will work to determine the structure of another conformation of the protein that explains the other half of the process: how material is delivered into the cell.

Chen’s research group is associated with the Purdue Cancer Center, one of just seven National Cancer Institute-designated basic research facilities in the United States. It was established in 1976 and attempts to help cancer patients by identifying new molecular targets and designing future agents and drugs for effectively detecting and treating cancer. The center also is affiliated with the Oncological Science Center in Purdue’s Discovery Park.

Chen and Davidson also are members of Purdue’s Center for Basic and Applied Membrane Sciences. The center was established to utilize the expertise of 45 faculty members. The center fosters collaboration in 12 different areas of basic and applied membrane sciences, with the mission to improve basic biochemical and biophysical understanding of membrane sciences, and to develop applications that are important in medicine, physiology and engineering.

The National Institutes of Health, Welch Foundation, Pew Scholar Program and a postdoctoral fellowship from the American Heart Association supported this work.

Adapted from materials provided by Purdue University.

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Honey bees with pupal brood cells. Honeybee larvae produce silk to reinforce the wax cells in which they pupate. (Credit: Nick Pitsas, CSIRO)

Moths and butterflies, particularly silkworms, are well known producers of silk. And we all know spiders use it for their webs. But they are not the only invertebrates who make use of the strength and versatility of silk.

Dr Tara Sutherland and her group from CSIRO Entomology are looking at silks produced by other insects and the results of their recent work have been published in Molecular Biology and Evolution, in the paper Conservation of Essential Design Features in Coiled Coil Silks.

“Most people are unaware that bees and ants produce silk but they do and its molecular structure is very different to that of the large protein, sheet structure of moth and spider silk. The cocoon and nest silks we looked at consist of coiled coils - a protein structural arrangement where multiple helices wind around each other. This structure produces a light weight, very tough silk,” she says.

“We had already identified the honeybee silk genes,” says Dr Sutherland, “and now we have identified and sequenced the silk genes of bumblebees, bulldog ants and weaver ants, and compared these to honeybee silk genes. This let us identify the essential design elements for the assembly and function of coiled coil silks”.

“To do this, we identified and compared the coiled coil proteins from cocoon and nest silks from species which span the evolutionary tree of the social Hymenoptera (bees, ants and wasps),” she says.

Bees and ants produce high-performance silk and, although the silks in all these species are produced by the larvae and by the same glands, they use them differently.

Honeybee larvae produce silk to reinforce the wax cells in which they pupate, bulldog ant larvae spin solitary cocoons for protection during pupation, bumblebee larvae spin cocoons within wax hives (the cocoons are reused to store pollen and honey), and weaver ants use their larvae as ‘tools’ to fasten fresh plant leaves together to form large communal nests..

These groups of insects have evolved silks that are very tough and stable in comparison to the classical sheet silks and it is probable that the evolution of this remarkable material has underpinned the success of the social Hymenoptera.

Coiled coil silks are common in aculeate social insects i.e. those that have stings but not in aculeate parasitic wasps. These social insects are higher up the evolutionary tree and the coiled coil silks appear to have evolved about 155 million years ago.

The silk research is part of the joint CSIRO and Grains Research & Development Corporation (GRDC) Crop Biofactories Initiative (CBI).

Adapted from materials provided by CSIRO Australia.

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Speaking November 8 at the American Academy of Dermatology’s (Academy) SKIN academy, dermatologist Zoe D. Draelos, MD, FAAD, from High Point, N.C., discussed the most common causes of hair damage, including how to prevent it and ways to maintain healthy hair as we age.

“It’s important to understand that hair is nonliving and cannot be repaired once it is injured,” said Dr. Draelos. “As we get older, hair growth slows down and the cosmetic beauty of our hair decreases. Hair loss that occurs from continual hair breakage over the years is a serious cosmetic concern for many women, so the key is to prevent this damage by stopping the cycle of over-processing and over-grooming our hair and selecting hair care products with proven hair-health benefits.”

In Our 20s

While age-wise our hair should be at its healthiest in our 20s, Dr. Draelos noted that some young women fall prey to yo-yo dieting or fad diets at this age – which can wreak havoc on hair. For hair to be healthy, it needs nourishment in the form of protein, vitamins and minerals from the foods we eat.

“Hair is a sign of our general overall health,” said Dr. Draelos. “When a person has an eating disorder or is omitting certain foods from her diet – such as meat – this can adversely affect the health and appearance of the hair. Hair that is not getting enough nutrition from the foods we eat doesn’t grow well and it won’t have that radiant, healthy glow.”

Since meat is an excellent source of protein, which is important for hair health, vegetarians need to be sure to supplement their diet with other complete, or whole, sources of protein. Complete proteins are those that contain all of the essential amino acids for the dietary needs of humans. Dr. Draelos advised vegetarians to consume milk products, such as cheese, milk or yogurt, for complete proteins.

She also cautioned that some proteins in vegetables are not complete sources of protein and taking multivitamins will not help make up for a lack of dietary protein, as they do not contain protein.

Another hair concern for women in their 20s, and 30s, is what happens to their hair when they stop taking birth control pills. Dr. Draelos explained that when estrogen levels fall during this process, hair will fall out.

“Sometimes when a woman notices her hair is falling out, she might not link it to a certain event, such as stopping oral contraceptives, since hair typically doesn’t shed for about three months after an occurrence that is happening inside the body,” added Dr. Draelos. “I tell my patients that our hair is like looking at tree rings – it’s an indication of what’s happened in the past.”

In Our 30s

For women in their 30s, pregnancy is a common life event that can affect hair health. During pregnancy, all of the hair follicles on the scalp are usually signaled to grow – resulting in luxurious, radiant-looking hair. However, in the six months following delivery, hair sheds.

“Many times, some of the hair that is shed post-pregnancy may eventually re-grow,” said Dr. Draelos. “However, in women who have female-pattern hair loss, the hair may not re-grow. Those women who have an inherited tendency towards female-pattern hair loss should seek dermatologic help at that point.”

In Our 40s

Although hair dyes are popular for women of all ages, women in their 40s may be more likely to turn to hair color as a way to camouflage gray hair that typically starts to appear at this age. Dr. Draelos explained that gray hair occurs when the pigment cells in the body stop producing pigments, which is a s