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The levels of contamination to water and sediment in Frenchman’s Bay in Pickering, Ontario greatly exceed provincial water quality standards, in some cases by as much as 250 per cent, according to a new study by researchers at the University of Toronto Scarborough. This is largely due to large amounts of road salt applied in winter, especially to Highway 401, the study finds.

Roads, parking lots and railways are the primary source of contaminated water and sediment and a decline in aquatic life in the watershed and lagoon, according to a recent article in Sedimentary Geology written by geology professor Nick Eyles and recent PhD graduate Mandy Meriano.

The densely populated area along Highway 401 and its accompanying traffic volume have profoundly affected the geology and characteristics of water in the bay and nearby city, according to the article, “Road-impacted sediment and water in a Lake Ontario watershed and lagoon, City of Pickering, Ontario, Canada: An example of urban basin analysis.” The growing city of 100,000 people is sprawled across a densely urbanized watershed that has been “hardened” by roads, rail lines, buildings and parking lots, the authors write.

“Our findings are pretty dramatic, and the effects are felt year round,” says Eyles. “This is a really bad news story about the relentless chemical assault on a watershed, with bleak implications that go far beyond the lagoon itself. We now know that 3,600 tonnes of road salt end up in that small lagoon every winter from direct runoff in creeks and effectively poison it for the rest of the year. The future of Frenchman’s Bay is not bright, but this also affects the Great Lakes.”
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Chemicals that helped solve a global environmental crisis in the 1990s — the hole in Earth’s protective ozone layer — may be making another problem — acid rain — worse, scientists are reporting. Their study on the chemicals that replaced the ozone-destroying chlorofluorocarbons (CFCs) once used in aerosol spray cans, air conditioners, refrigerators, and other products, appears in ACS’ Journal of Physical Chemistry A, a weekly publication.

Jeffrey Gaffney, Carrie J. Christiansen, Shakeel S. Dalal, Alexander M. Mebel and Joseph S. Francisco point out that hydrochlorofluorocarbons (HCFCs) emerged as CFC replacements because they do not damage the ozone layer. However, studies later suggested the need for a replacement for the replacements, showing that HCFCs act like super greenhouse gases, 4,500 times more potent than carbon dioxide. The new study adds to those concerns, raising the possibility that HCFCs may break down in the atmosphere to form oxalic acid, one of the culprits in acid rain.
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Climate change is one reason malaria is on the rise in some parts of the world, new research finds, but other factors such as migration and land-use changes are likely also at play. The research, published in The Quarterly Review of Biology, aims to sort out contradictions that have emerged as scientists try to understand why malaria has been spreading into highland areas of East Africa, Indonesia, Afghanistan and elsewhere.

“We assessed … conclusions from both sides and found that evidence for a role of climate in the dynamics is robust,” write study authors Luis Fernando Chaves from Emory University and Constantianus Koenraadt of Wageningen University in the Netherlands. “However, we also argue that over-emphasizing a role for climate is misleading for setting a research agenda, even one which attempts to understand climate change impacts on emerging malaria patterns.”

Malaria, a parasitic disease spread to humans by mosquitoes, is common in warm climates of Africa, South America and South Asia. The development and survival, both of the mosquito and the malaria parasite are highly sensitive to daily and seasonal temperature patterns and the disease has traditionally been rare in the cooler highland areas. Over the last 40 years, however, the disease has been spreading to the highlands, and many studies link the spread to global warming. But that conclusion is far from unanimous. Other studies have found no evidence of warming in highland regions, thus ruling out climate change as a driver for highland malaria.

Chaves and Koenraadt re-examined more than 70 of these studies. They found that the studies ruling out a role for climate change in highland malaria often use inappropriate statistical tools, casting doubt on their conclusions.

For example, an oft-cited 2002 study of the Kericho highlands of western Kenya found no warming trend in the area. But when Chaves and Koenraadt ran the same temperature data from that study through three additional statistical tests, each test indicated a significant warming trend. Similar statistical errors plague other comparable studies, the researchers say.
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Toxin Does Not Affect MRSA-Induced Pneumonia

A group led by Dr. James M. Musser at the Center for Molecular and Translational
Human Infectious Diseases Research of The Methodist Hospital Research Institute
in Houston, Texas has demonstrated that the cytotoxin Paton-Valentine leukocidin
(PVL) does not affect methicillin-resistant Staphlococcus aureus (MRSA)-induced
pneumonia. Their report can be found in the March 2010 issue of The American
Journal of Pathology.

Community-associated-MRSA causes a wide spectrum of infections, ranging from
mild skin problems to fatal invasive diseases. MRSA spreads rapidly from initial
topical symptoms to affect vital organs, often resulting in widespread
infection, toxic shock, and ‘flesh eating’ pneumonia. MRSA is resistant to
traditional anti-staphylococcal beta-lactam antibiotics and is therefore much
more difficult to treat.

The cytolytic toxin PVL is a CA-MRSA virulence factor that has been
epidemiologically associated with the development of invasive, and sometimes
fatal, pneumonia in affected patients and has therefore become a target for new
therapeutics. To explore the role of PVL in invasive MRSA, Olsen et al examined
both wild-type and PVL-deficient MRSA in a model of CA-MRSA pneumonia. They
found no effect of PVL on virulence in MRSA-associated pneumonia, as a PVL-mutated
strain caused similar lower respiratory tract pathology as a wild-type strain.
These data highlight the importance of context in the pathogenesis of MRSA-associated
pneumonia.

Addition studies are underway by Dr. Musser and colleagues “to test the
hypothesis that PVL enhances pathogenesis during influenza virus co-infection.
These studies are especially important in the context of the recent global
spread of a H1N1 influenza strain and widespread concerns about a detrimental
effect on human health.”
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A laser technique best known for its use to remove unwanted tattoos from the
skin is finding a second life in preserving great sculptures, paintings and
other works of art, according to an article in ACS’ monthly journal, Accounts of
Chemical Research. The technique, called laser ablation, involves removing
material from a solid surface by vaporizing the material with a laser beam.

Salvatore Siano and Renzo Salimbeni point out that laser cleaning of artworks
actually began about 10 years before the better known medical and industrial
applications of the technique. Doctors, for example, use laser ablation in
medicine to remove unwanted tattoos from the skin. In industry, the technique
can remove paints, coatings and other material without damaging the underlying
surface.

In the article, the scientists note that laser ablation has had an important
impact in preserving the world’s cultural heritage of great works of art. They
describe the latest advances in laser cleaning of stone and metal statues and
wall paintings, including masterpieces like Lorenzo Ghiberti’s Porta del
Paradiso and Donatello’s David. They also discuss encouraging results of laser
cleaning underwater for materials that could deteriorate if exposed to air.

Chemists at UC San Diego and statisticians at Harvard University have developed a novel way to trace mutations in HIV that lead to drug resistance. Their findings, once expanded to the full range of drugs available to treat the infection, would allow doctors to tailor drug cocktails to the particular strains of the virus found in individual patients.

“We want to crack the code of resistance,” said Wei Wang, associate professor chemistry and biochemistry at UC San Diego who led the collaboration along with Jun Liu of Harvard. The team reports their work in this week’s early online edition of the Proceedings of the National Academy of Sciences.
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Researchers from the Helmholtz-Zentrum Berlin für Materialien und Energie (HZB), in cooperation with colleagues from Oxford and Bristol Universities, as well as the Rutherford Appleton Laboratory, UK, have for the first time observed a nanoscale symmetry hidden in solid state matter. They have measured the signatures of a symmetry showing the same attributes as the golden ratio famous from art and architecture. The research team is publishing these findings in Science on the 8. January.
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A team of researchers from the University of Girona and the Max Planck Institute in Germany has shown that some mathematical algorithms provide clues about the artistic style of a painting. The composition of colours or certain aesthetic measurements can already be quantified by a computer, but machines are still far from being able to interpret art in the way that people do.

How does one place an artwork in a particular artistic period? This is the question raised by scientists from the Laboratory of Graphics and Image in the University of Girona and the Max Planck Institute for Biological Cybernetics, in Germany. The researchers have shown that certain artificial vision algorithms mean a computer can be programmed to “understand” an image and differentiate between artistic styles based on low-level pictorial information. Human classification strategies, however, include medium and high-level concepts.
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Using literature written by Thomas Hardy, DH Lawrence and Herman Melville, physicists in Sweden have developed a formula to detect different authors’ literary ‘fingerprints’.

New research published today, Thursday 10 December, in New Journal of Physics (co-owned by the Institute of Physics and German Physical Society), describes a new concept from a group of Swedish physicists from the Department of Physics at Umeå University called the meta book which uses the frequency with which authors use new words in their literature to find distinct patterns in authors’ written styles. 
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Providence, RI—”Mathematics links Art and Science in one great enterprise, the human attempt to make sense of the universe.”

So writes Abel Prizewinner and Fields Medalist Sir Michael F. Atiyah in the January 2010 Notices of the American Mathematical Society. The theme of the issue is creativity in mathematics.

Mathematicians have always felt a strong creative aspect in their subject, but only in recent years has the flowering of connections between mathematics and the arts made this aspect apparent to the general public. The collection of three articles in the Notices, together with Atiyah’s short introductory piece, explore some of the various ways in which art and beauty appear in mathematics.
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