A Bridge Too Far? Stark Warning From History Over Plans For 'Inhabited' London Bridge  

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On July 11, public celebrations will mark the 800th anniversary of the completion of London Bridge. Now, a new study at the University of Leicester has uncovered a tale of corruption, mismanagement, financial crisis and a property crash that resulted in the downfall of the Old London Bridge -- the capital’s last ‘living bridge’.


The research, which is due to be published in the London Journal, provides a stark warning from history as plans are discussed for a new ‘inhabited’ London Bridge – between Waterloo and Blackfriars – with luxury flats, shops and restaurants. London Mayor Boris Johnson has revived plans for the £80m scheme.

But doctoral research conducted by Mark Latham at the University of Leicester’s Centre for Urban History discovered the houses built on the Old London Bridge to attract the gentry didn’t have the pulling power as expected. This combined with an economic slump and other factors to ensure that the grand vision of an inhabited bridge across the Thames was not sustainable.

“Old London Bridge is familiar to many of us in the form of the nursery rhyme “London Bridge is fallen down”, said Mr Latham, “but what is not generally known is why commerce and housing on the bridge did collapse.

“It was previously assumed by historians that the removal of the structures from the Bridge was part of a more general movement within the Corporation of London to “improve” the City via a series of infrastructure projects. However it is clear from my research that a far more complex and intriguing set of factors were at play.”

The removal of the houses and shops from Old London Bridge occurred in 1756. Mr Latham’s study has examined why.

He said: “I am fascinated by the question of why the houses were removed from the Bridge as in medieval times they were viewed as one of London’s great attractions, and the rental income from the houses on the Bridge, alongside others within the City of London, financed the maintenance of the structure.

“What I discovered was that the organisation that managed the bridge at that time was plagued with incompetent management and corruption. Both workmen and their managers charged inflated prices for materials and labour, the management left rents uncollected, and on several occasions the workmen were found to have deliberately and almost fatally damaged the Bridge in order to charge for its repair.

“Furthermore, managers often paid for improvements to their own houses out of the coffers of the Trust running the Bridge.”

Problems were compounded by a “highly risky, costly and poorly timed project” undertaken in the teeth of a credit crisis to construct a series of gentrified houses on the Bridge in the belief that such houses would prove attractive to middle class Londoners and increase the organisation’s rental income. However, the authorities had grossly miscalculated the demand for such properties and the houses attracted only a handful of tenants.

A London wide property crash ensued and soon the Trust running the bridge was haemorrhaging income, the maintenance budget for the Bridge itself was being squeezed and so the vacant houses on the Bridge began to rapidly fall into a state of dangerous disrepair. London Bridge was indeed close to being “fallen down”, said Mr Latham.

“At this point reality dawned on the members of the Trust, and they faced up to the fact that it was no longer financially viable to maintain structures on the Bridge, and by the early 1755 they had begun to petition Parliament in a desperate plea for the money to fund their demolition.”

One further interesting insight from the study is that the removal of the houses and businesses from the Bridge marks a break from London’s medieval past.

Said Mr Latham: “The renovation of the Bridge in the mid eighteenth century was such an important event in the history of London as in many ways the demolition of these characterful medieval houses and the subsequent transformation of the Bridge into the type of bland utilitarian functional structure - very similar to the London Bridge we see today - represents a rupture with London’s medieval past and can be taken as symbolic of London’s emergent modernity.”


Single Molecules As Electric Conductors  

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Researchers from Graz University of Technology, Humboldt University in Berlin, M.I.T., Montan University in Leoben and Georgia Institute of Technology report an important advance in the understanding of electrical conduction through single molecules.


Minimum size, maximum efficiency: The use of molecules as elements in electronic circuits shows great potential. One of the central challenges up until now has been that most molecules only start to conduct once a large voltage has been applied. An international research team with participation of the Graz University of Technology has shown that molecules containing an odd number of electrons are much more conductive at low bias voltages. These fundamental findings in the highly dynamic research field of nanotechnology open up a diverse array of possible applications: More efficient microchips and components with considerably increased storage densities are conceivable.

One electron instead of two: Most stable molecules have a closed shell configuration with an even number of electrons. Molecules with an odd number of electrons tend to be harder for chemists to synthesize but they conduct much better at low bias voltages. Although using an odd rather than an even number of electrons may seem simple, it is a fundamental realization in the field of nanotechnology – because as a result of this, metal elements in molecular electronic circuits can now be replaced by single molecules. “This brings us a considerable step closer to the ultimate minitiurization of electronic components”, explains Egbert Zojer from the Institute for Solid State Physics of the Graz University of Technology.

Molecules instead of metal

The motivation for this basic research is the vision of circuits that only consist of a few molecules. “If it is possible to get molecular components to completely assume the functions of a circuit’s various elements, this would open up a wide array of possible applications, the full potential of which will only become apparent over time. In our work we show a path to realizing the highly electrically conductive elements”, Zojer excitedly reports the momentous consequences of the discovery.

Specific new perspectives are opened up in the field of molecular electronics, sensor technology or the development of bio-compatible interfaces between inorganic and organic materials: The latter refers to the contact with biological systems such as human cells, for instance, which can be connected to electronic circuits in a bio-compatible fashion via the conductive molecules.


Apollo 11 Moon Rocks Still Crucial 40 Years Later, Say Researchers  

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A lunar geochemist at Washington University in St. Louis says that there are still many answers to be gleaned from the moon rocks collected by the Apollo 11 astronauts on their historic moonwalk 40 years ago July 20.


And he credits another WUSTL professor for the fact that the astronauts even collected the moon rocks in the first place.

Randy L. Korotev, Ph.D., a research professor in the Department of Earth and Planetary Sciences in Arts & Sciences, has studied lunar samples and their chemical compositions since he was an undergraduate at the University of Wisconsin and "was in the right place at the right time" in 1969 to be a part of a team to study some of the first lunar samples.

"We know even more now and can ask smarter questions as we research these samples," says Korotev, who is mainly interested in studying the impact history of the moon, how the moon's surface has been affected by meteorite impacts and the nature of the early lunar crust.

"There are still some answers, we believe, in the Apollo 11 mission.

"We went to the moon and collected samples before we knew much about the moon. We didn't totally understand the big concept of what the moon was like until early 2000 as a result of missions that orbited the moon collecting mineralogical and compositional data.

"It's only been fairly recently that we decided that we should look closer at these Apollo 11 samples."

Korotev credits the late Robert M. Walker, Ph.D., Washington University's McDonnell Professor of Physics in Arts & Sciences, and a handful of other scientists for the fact that there are even moon samples to study.

"Bringing samples back from the moon wasn't the point of the mission," says Korotev. "It was really about politics. It took scientists like Bob Walker to bring these samples back — to show the value of them for research.

"Bob convinced them to build a receiving lab for the samples and advised them on the handling and storage of them.

"We didn't' go to the moon to collect rocks, so we scientists are really lucky that we have this collection."

Korotev points out that by the last Apollo mission — Apollo 17 — one of the astronauts onboard was a geologist, Harrison H. Schmitt.

WUSTL's moon history

Walker was recruited to serve on the scientific team that advised NASA on the handling and distribution of moon rocks and soil samples from the first Apollo missions. That team distributed Apollo 11 samples to some 150 laboratories worldwide, including WUSTL.

Walker also briefed those early astronauts about what to expect on the rocky, dusty moon surface.

In an interview some months after the first moon samples arrived in WUSTL's space sciences lab, Walker recalled the excitement of that momentous day in 1969: "We felt just like a bunch of kids who were suddenly given a brand new toy store ... there was so much to do, we hardly knew where to begin."

Ghislaine Crozaz, Ph.D., professor of earth and planetary sciences emerita in Arts & Sciences at Washington University and a member of Walker's space sciences group that was one of those selected to study the first lunar samples, says the event is "as vivid in my mind as if it had happened yesterday."

Crozaz says that the team studied the cosmic rays and radiation history of the lunar samples mainly using nuclear particle tracks, which were revealed by techniques invented by Walker.

"After we received the samples in early September, we worked like hell until the First Lunar Science Conference in early January 1970 in Houston, where we arrived with our Science paper after having worked 'incommunicado' for 4 months."

In their study of the lunar materials, Walker's laboratory led the way in deciphering their record of lunar, solar system and galactic evolution. Of special importance was the information they gave on the history of solar radiation and cosmic rays.

Crozaz, who later became Walker's wife, says the lunar samples provided insights into the history of the solar system that couldn't be achieved at the time by looking at meteorites found on Earth. The intense heat encountered during their passage through the atmosphere would have erased much of the record of radiation the meteorites carried.

The Apollo 11 samples — and samples from almost every Apollo mission until the last one in December 1972 — have been securely housed on the 4th floor of the physics department's Compton Laboratory and used by numerous WUSTL researchers, including many members of the McDonnell Center for the Space Sciences. The McDonnell Center was established in 1974, with Walker as its inaugural director.

Today, the remaining lunar samples in Compton Hall that arrived in 1969 from the Apollo 11 mission and from subsequent Apollo missions in the 1970s are being painstakingly prepared for a return trip to Houston to NASA's moon rocks repository, the Lunar Sample Building at the Lyndon B. Johnson Space Center in Houston, Texas.

"The samples have been exhaustively analyzed and numerous papers have been published showing interesting research results," says Ernst K. Zinner, Ph.D., research professor of physics and of earth and planetary sciences, who joined Walker's lab in 1972 studying Apollo mission samples before focusing on analysis of stellar dust grains found in primitive meteorites.

"We have finished analyzing these particular samples and we're focusing on other extraterrestrial samples. In a sense, our lab in Compton has moved from the moon to the stars in our research interests.

"It is a great and serious responsibility to hold and guard these samples, which are absolutely irreplaceable."

In the meantime, in the Earth and Planetary Sciences Building, next door to Compton Hall, Korotev, who received his Apollo 11 samples from NASA much later — not until 2005 — still has much work to do with his samples, which have been chemically analyzed and are sealed in tubes and securely stored away for now.

"You can look at the moon and know that the moon has been hit a lot by very large meteorites," says Korotev. "We know this occurred some 3.9 billion years ago.

"We don't know, however, the history of large meteorites hitting the Earth — we can't see those impacts because they would have been erased by Earth's active geology.

"We want to see if meteorite bombardment on the moon coincided with what was happening on Earth, and, in turn, with life starting on Earth," says Korotev, who as a 20-year-old chemistry major in 1969, decided his career path after working with the Apollo 11 rocks.

"The whole experience decided my career. I went to graduate school in 1971 to study lunar geochemistry so that I'd know how to interpret the chemical data we obtained in terms of lunar geology. That's what I'm still doing!"


First Look At The Apollo Landing Sites  

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The imaging system on board NASA's Lunar Reconnaissance Orbiter (LRO) recently had its first of many opportunities to photograph the Apollo landing sites. The Lunar Reconnaissance Orbiter Camera (LROC) imaged five of the six Apollo sites with the narrow angle cameras (NACs) between July 11 and 15, within days of the 40th anniversary of the Apollo 11 mission.


The early images obtained by LROC, operated by Arizona State University Professor Mark Robinson, show the lunar module descent stages left behind by the departing astronauts. Their locations are made evident by their long shadows, which result from a low sun angle at the time of collection.

"In a three-day period we were able to image five of the six Apollo sites – the LROC team anxiously awaited each image," says LROC Principal Investigator Mark Robinson, professor in the School of Earth and Space Exploration in ASU's College of Liberal Arts and Sciences. "Of course we were very interested to get our first peek at the lunar module descent stages just for the thrill – and to see how well the cameras had come into focus."

The orbiter's current elliptical orbit resulted in image resolutions from the NACs that were slightly different for each site but were all about four feet per pixel. Since the deck of the descent stage is about 14 feet in diameter, the Apollo relics themselves fill about four pixels. However, because the Sun was low to the horizon when the images were acquired, even subtle variations in topography create long shadows. Standing just over ten feet above the surface, each Apollo descent stage creates a distinct shadow that fills roughly 20 pixels.

"For the five landing site images photographed by LROC, the biggest variables are spacecraft altitude (ground scale) and time of day, which translates into signal strength," explains Robinson. "In the current collection of images the best discrimination of features is in the Apollo 14 scene even though the highest resolution picture covers the Apollo 16 site."

Compared to the other landing site images, the image of the Apollo 14 site revealed additional details. The Apollo Lunar Surface Experiment Package (ALSEP), a set of scientific instruments placed by the astronauts at the landing site, is discernable, as are the faint trails between the descent stage and ALSEP left by the astronauts' footprints.

Though it had been expected that LRO would be able to resolve the remnants of the Apollo missions, these first images came prior to the spacecraft reaching its final mapping orbit. As the orbit of LRO is lowered, LROC will receive many more opportunities to image the landing sites in the weeks to come. The resolution of future LROC images of these sites will improve by two to three times.

The timing of these images being captured is notable as it occurred only days before the 40-year anniversary of NASA's Apollo 11 mission that first put humans on the moon. Though these pictures provide a reminder of one of humankind's greatest technological achievements, LRO's primary focus is paving the way for future exploration. By returning detailed lunar data the LRO mission will help NASA identify safe and compelling landing sites for future explorers, locate potential resources, describe the moon's radiation environment and demonstrate new technologies.


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The Wildlife Conservation Society announced today that critically endangered alligators in China have a new chance for survival. The WCS's Bronx Zoo, in partnership with two other North American parks and the Department of Wildlife Conservation and Management of the State Forestry Administration of China, has successfully reintroduced alligators into the wild that are now multiplying on their own.


The alligator hatchlings—15 in number—are the offspring of a group of alligators that includes animals from the Wildlife Conservation Society's Bronx Zoo. The baby alligators represent a milestone for the 10-year effort to reintroduce the Chinese alligator on Chongming Island, located at the mouth of China's Yangtze River.

The announcement was made at the International Congress for Conservation Biology, convened by the Society for Conservation Biology in Beijing, China (July 11-16).

"We are grateful to our Chinese partners for their commitment to reintroduce Chinese alligators back into the wild," said Dr. Steven E. Sanderson, President and CEO of the Wildlife Conservation Society. "WCS has championed careful wildlife reintroductions for more than a century. The reintroduction of Chinese alligators is a great example of how WCS partners with governments and local communities around the world to save wildlife and wild places."

"This is fantastic news," said WCS researcher Dr. John Thorbjarnarson, one of the world's foremost experts on crocodilians and a participant in the project. "The success of this small population suggests that there's hope for bringing the Chinese alligator back to some parts of its former distribution."

Plans to reintroduce Chinese alligators started in 1999 with a survey conducted by WCS, the Anhui Forestry Bureau, and the East China Normal University in Anhui Province, the only remaining location where the reptiles are still found in the wild in what is a small fraction of the alligator's former range. The results of the survey were dire, with an estimate of fewer than 130 animals in a declining population.

An international workshop on the species was held in 2001, followed by recommendations for the reintroduction of captive bred alligators. The first three animals released in Hongxing Reserve of Xuancheng County in Anhui in 2003 were from the Anhui Research Center of Chinese Alligator Reproduction (ARCCAR).

To ensure the maximum genetic diversity for the effort, project participants imported 12 more animals to Changxing Yinjiabian Chinese Alligator Nature Reserve from North America, including four from the Bronx Zoo. From this group, three animals from the U.S. were released in 2007 along with three more alligators from Changxing. The alligators were given health examinations by veterinary professionals from WCS's Global Health Program and the Shanghai Wildlife Zoo and fitted with radio transmitters for remote monitoring before being released.

Experts reported that the reintroduced alligators successfully hibernated, and then in 2008, bred in the wild.

With a former range that covered a wide watershed area of East China, the Chinese alligator—or "tu long," which means "muddy dragon"—is now listed as "Critically Endangered" on IUCN's Red List of Threatened Species and is the most threatened of the 23 species of crocodilians in the world today. It is one of only two alligator species in existence (the other is the better known, and much better off, American alligator).

The Yangtze River, where the reintroduction of these alligators took place, is the third longest river in the world (after the Amazon and the Nile) and is China's most economically important waterway. The world's largest hydro-electric dam—the Three Gorges Dam—is also located on the river. The high levels of development along the river have become a challenge for native wildlife; in 2006, a comprehensive search for the Yangtze River dolphin, or baiji, didn't find any, although one isolated sighting of a dolphin was made in 2007.

Other participants in the project include the East China Normal University, Shanghai Forestry Bureau, Changxing Yinjiabian Chinese Alligator Nature Reserve, and Wetland Park of Shanghai Industrial Investment (Holdings) Co. Ltd.

The project is being supported by the Ocean Park Conservation Foundation, Hong Kong.


King Crabs Go Deep To Avoid Hot Water  

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Researchers from the University of Southampton have drawn together 200 years' worth of oceanographic knowledge to investigate the distribution of a notorious deep-sea giant - the king crab. The results, published this week in the Journal of Biogeography, reveal temperature as a driving force behind the divergence of a major seafloor predator; globally, and over tens of millions of years of Earth's history.


In deep seas all over the world, around 100 species of king crabs live largely undiscovered. The fraction that have been found includes some weird and wonderful examples - Paralomis seagrantii has its eight walking legs and claws entirely covered in long fur-like setae; while related group Lithodes megacanthus grows to lengths of 1.5 metres, and has 15-20-cm long defensive spines covering its body. At temperatures of around 1- 4ºC, these crabs thrive in some of the colder waters on Earth; living and growing very slowly, probably to very old ages. Only in the cooler water towards the poles are king crabs found near the water surface - though temperatures found around some parts of the Antarctic (below 1ºC) are too extreme for their survival.

A paper, published 15 years ago in Nature is thought to show that king crabs evolved from shell-bound hermit crabs - similar to the familiar shoreline animals. Soft-bodied, but shell-free intermediate forms are found only in the shallow waters off Japan, Alaska, and Western Canada.

By looking at 200 years' worth of records from scientific cruises and museum collections, Sally Hall and Dr Sven Thatje from the University of Southampton's School of Ocean and Earth Science at the National Oceanography Centre, Southampton discovered that the soft-bodied forms can live at temperatures about ten degrees higher than the hard-bodied forms, but that both groups can only reproduce when temperature is between 1ºC up to 13-15ºC.

"It seems that most shallow-water representatives of this family are trapped in the coastal regions of the North Pacific because the higher sea surface temperatures further south prevent them from reproducing successfully and spreading," said Dr Thatje.

In order to leave this geographic bottleneck and spread around the world, the shallow water ancestors of current deep-sea groups had to go deep and adapt to the challenges of life in the deep sea. The process of adaptation to constant low temperatures (1-4ºC) prevailing in the deep sea seems to have narrowed the temperature tolerance range of the crabs where they have emerged to the surface waters in the Southern Hemisphere. With differences of only a couple of degrees in temperature affecting the distribution of the king crab, it is difficult to predict the consequences of range expansion in the warming waters around the Antarctic Peninsular region.

King crabs are of great commercial value, and fisheries are established in high latitude regions of both hemispheres. "Understanding their evolutionary history and ecology is key to supporting sustainable fisheries of these creatures," said research student Sally Hall. She adds: "Recent range extensions of king crabs into Antarctica, as well as that of the red king crab Paralithodes camtchaticus in the Barents Sea and along the coast off Norway emphasise the responsiveness of this group to rapid climate change."

This study reveals temperature as a driving force behind the speciation and radiation of a major seafloor predator globally and over tens of millions of years of Earth's history.

The study has been supported by the National Environment Research Council (UK) through a PhD studentship to Sally Hall, and a Research Grant from the Royal Society awarded to Dr Thatje.


Ecologist Brings Century-old Eggs To Life To Study Evolution  

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Suspending a life in time is a theme that normally finds itself in the pages of science fiction, but now such ideas have become a reality in the annals of science.


Cornell ecologist Nelson Hairston Jr. is a pioneer in a field known loosely as "resurrection ecology," in which researchers study the eggs of such creatures as zooplankton -- tiny, free-floating water animals -- that get buried in lake sediments and can remain viable for decades or even centuries. By hatching these eggs, Hairston and others can compare time-suspended hatchlings with their more contemporary counterparts to better understand how a species may have evolved in the meantime.

The researchers take sediment cores from lake floors to extract the eggs; the deeper the egg lies in the core, the older it is. They then place the eggs in optimal hatching conditions, such as those found in spring in a temperate lake, and let nature take its course.

"We can resurrect them and discover what life was like in the past," said Hairston, who came to Cornell in 1985 and is a professor and chair of Cornell's Department of Ecology and Evolutionary Biology. "Paleo-ecologists study microfossils, but you can't understand much physiologically or behaviorally" with that approach, he said.

Hairston first became interested in the possibilities of studying dormant eggs in the late 1970s, when he was an assistant professor of zoology at the University of Rhode Island. There, he noticed that the little red crustaceans -- known as copepods -- in the pristine lake behind his Rhode Island home disappeared in the summer, only to return as larvae in the fall.

The observation prompted him to study why they disappear, research that revealed the copepods stay active under the ice in the winter, but they die out as their eggs lie dormant on the lake floor through the summer when the lake's fish are most active. When the fish become less active in the fall, larvae hatch from the eggs, and the copepods continue their life cycle.

This time suspension, where zooplankton pause their life cycles to avoid heavy predation or harsh seasonal and environmental conditions, also increases a species' local gene pool, with up to a century's worth of genetic material stored in a lake bed, Hairston said. When insects, nesting fish and boat anchors stir the mud, they can release old eggs that hatch and offer a wider variety of genetic material to the contemporary population.

In 1999 Hairston and colleagues published a paper in Nature that described how 40-year-old resurrected eggs could answer whether tiny crustaceans called Daphnia in central Europe's Lake Constance had evolved to survive rising levels of toxic cyanobacteria, known as blue-green algae. In the 1970s, phosphorus levels from pollution rose in the lake, increasing the numbers of cyanobacteria. The researchers hatched eggs from the 1960s and found they could not survive the toxic lake conditions, but Daphnia from the 1970s had adapted and survived.

Hairston and colleagues have organized a resurrection ecology symposium in September 2009, in Herzberg, Switzerland, to bring together researchers in this growing new field.


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