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The Alchemist takes a virtual trip to New Mexico this week to learn of resistant bacteria. He also discovers that counter intuitively putting certain zeolites under pressure can open up the entrances to their pores. In geochemistry, we learn why copper is not found so commonly at the Earth's surface and could point the way to finding new sources. New technology could kick up a stink in Hollywood by finding a way to detect mould growth on old film reels. Graphene is in the news again, this time putting it under strain apparently makes it behave as if it were in a magnetic field. Finally, the GHS has released its new chemical hazard symbol for carcinogens to no little controversy.




The Lechuguilla Cave in New Mexico, one of the deepest and largest in the world has remained isolated from human contact for millions of years and yet scientists at McMaster University in Hamilton, Ontario, have discovered a whole tranche of bacteria resistant to modern antibiotics in this remote environment. "Our study shows that antibiotic resistance is hard-wired into bacteria, it could be billions of years old, but we have only been trying to understand it for the last 70 years," explains research leader Gerry Wright. "This has important clinical implications. It suggests that there are far more antibiotics in the environment that could be found and used to treat currently untreatable infections."





Squeezing natrolite, a porous aluminosilicate zeolites mineral, can open up its pores allowing ions as large as europium (or perhaps uranium) inside. The phenomenon was discovered by an international team based at the University of South Carolina and Stanford University, USA and Yonsei University, Korea. "With natrolite, people have always said you can't get europium ions in there. But under pressure, you can," says USC's Thomas Vogt. The auxetic behavior may be counter-intuitive in that diamond anvil pressure opens a window for larger ions to migrate into the pores. The exchange of europium ions shows promise for nuclear waste processing as uranium ions are a similar size.





Apparently, nature conspires at scales both large and small - from the truly tectonic to molecular mundanity to keep Earth's copper buried many miles below ground. "Everything throughout history shows us that Earth does not want to give up its copper to the continental crust," explains Cin-Ty Lee of Rice University. "Both the building blocks for continents and the continental crust itself, dating back as much as 3 billion years, are highly depleted in copper." Lee and colleagues have investigated Earth’s arc magmas - the molten building blocks for continents - and looked at the xenoliths, rocks that formed deep inside Earth and were carried up to the surface in volcanic eruptions, to help them explain why surface copper is scarce. Their findings could help us locate hidden caches of the invaluable metal as ready supplies dwindle and the price of the raw metal soar.





Old movies do not age well…at least in terms of the chemical degradation of the film on which they are printed. Fungi are often to blame, digesting the material and generating noxious odors and unwatchable films in the process. Now, the UK’s North West Film Archive has worked with researchers at Manchester Metropolitan University (MMU) to find a way to detect these problematic odors and act as an early-warning system for fungal infection of film. The technology could alert conservators to a growing problem before it causes significant damage to the film and before odor compounds reach levels hazardous to human health.





Graphene is light, strong and has unusual optoelectronic properties. Now, researchers at the University of Arkansas and elsewhere have worked together to develop a technique for controlling the mechanical strain in freestanding graphene sheets over tiny squares of copper. The team suggests that controlling the strain of freestanding graphene could allow them to fine tune its properties for particular applications. “If you subject graphene to strain, you change its electronic properties,” says Salvador Barraza-Lopez. Inducing strain in the material causes it to behave as if it were in a magnetic field, a phenomenon that might be exploited in electromechanical systems.





The Globally Harmonized System of Classification and Labeling of Chemicals (GHS) is the new international standard for shipping and labeling chemicals so that their hazards are communicated in a logical fashion. The organization has now released a new symbol representing a carcinogenic hazard. The symbol is a red diamond within which is a silhouetted person emblazoned with a six-pointed device, not dissimilar to a cartoon snowflake, purportedly representing the growth of errant cancer cells and their spread. The new symbol has garnered some controversy as not being particularly logical nor representing carcinogenicity in a logical manner despite the organization's intentions.