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The Alchemist this week learns that almost $1 million has been earmarked for defense related research into a new type of fiber that could be woven into clothing, filters and respirators to protect employees and military personnel from toxic gases. In chemistry news xenon, a once "inert" gas, shows us once again that it is anything but unreactive, forming novel compounds with water molecules at the chilly temperature of 40 Kelvin. We also learn of a record-breaking band of gold containing 36 gold atoms in a ring, the effects of anthropogenic nitrogen on climate change, and the design of clinical trials for testing a novel Alzheimer's drug. Also this week, in biomimetic news, researchers have developed a peptide-based material that can mimic the properties of the ubiquitous and fibrous collagen molecule.

Cornell University's Juan Hinestroza is working with the U.S. government to create fabrics made of functional nanofibers that would decompose toxic industrial chemicals into harmless by-products. With funding of about $875,000 from the Department of Defense, Hinestroza and colleagues hope to create nanostructures that could be used in creating advanced air filtration and personal protection systems against airborne chemical threats. They will be useful in industrial plant, airplanes and personal respirators Hinestroza says. The first project, in collaboration with North Carolina State University, is aimed at understanding how very small electrical charges present in fibers and nanofibers can help in capturing nanoparticles, bacteria and viruses.

Trapping two xenon atoms within a water molecule is the unusual outcome of research by Leonid Khriachtchev at the University of Helsinki, Finland. Ever since Neil Bartlett synthesized the first noble gas compound, xenon hexafluoroplatinate, in 1962, chemists have constructed hundreds of molecules from the erstwhile "inert" elements, now known as noble gases. Khriachtchev's team blasted water and nitrous oxide with ultraviolet light. The constituent hydrogen and oxygen atoms, held within a solid matrix of xenon at 9 Kelvin, diffused slowly through the xenon on heating to 40 K. The resulting species identified by infrared spectroscopy were HXeO radicals and HXeOXeH hydrides. While these materials cannot be isolated from the matrix their formation suggests what might be possible in the future using other techniques.

A crown of 36 gold atoms locked together through gold-gold bonds has been synthesized by researchers at the Universities of Beijing, Hong Kong, and Nanjing, the biggest gold ring of its kind to date. Shu-Yan Yu, Yi-Zhi Li, and Vivian Wing-Wah Yam started with a six-atom system in which three of the gold atoms are linked in a triangle with a gold atom attached to each vertex. Organic ligands give the overall assembly a three-blade propeller structure. The team then hooked together six gold propellers using a self-assembly process. Within the resulting macrocyclic ring system, the gold atoms are arranged into a shape that resembles a crown: six double triangles bound to each other through two corners and the free double-corners pointing outward in a pattern that alternates above and below the plane of the ring.

Joseph Prospero of the University of Miami is an expert in aerosols, tiny particles carried around the globe on atmospheric eddies and winds. From 1980 onwards he and his colleagues established a network of island stations in the North and South Pacific Oceans to monitor the concentration of major aerosol species, mineral dust, nitrate, sulfate, and sea salt, which all play a role in climate. Now, a major study published in the journal Science, puts these long-term data sets into context and reveals how anthropogenic nitrogen may play a more significant role than previously thought. The nitrogen cycle is closely linked to the carbon cycle and the new study points to a closer link to changing nitrogen levels and effects on oceanic biology as well as atmospheric carbon dioxide levels. "All of us are concerned that the amount of anthropogenic nitrogen transported to the oceans will to continue to rise in the future," says Prospero.

Julian Keith of the University of North Carolina Wilmington and his colleagues have played a key role in designing, analyzing and interpreting a national clinical trial undertaken by Allon Therapeutics, Inc to investigate the efficacy of a new drug - AL-108 - for Alzheimer's disease. The drug may help people with mild cognitive impairment, a condition that is often a precursor to Alzheimer's disease. The key element in the study design was ensuring that preliminary testing established a solid cognitive ability baseline for each participant before the drug was administered, Keith explains. "We developed this study in a unique way," he adds, "We brought participants in for several testing sessions before they ever received the drug." This has provided a solid baseline against which improvements can be assessed.

Collagen is structural protein found in all higher organisms, but mimicking its unique chemical and physical properties remains a challenge for scientists. Now, researchers in the USA have turned to de novo design methods to create nanostructured biological materials that self-assemble from peptides and proteins into fibrous mimics of collagen. Shyam Rele, Elliot Chaikof and Vince Conticello of the Laboratory of Bio/Molecular Engineering and Advanced Vascular Technologies at Emory University School of Medicine have successfully designed and synthesized the first ever synthetic collagen peptide system using units just 36 amino acids long. The natural-looking D-periodicity of the synthetic collagen is approximately 18 nanometers. However, it is the high propensity for self-association through a nucleation-growth mechanism even at low concentration and neutral pH that make them most interesting from a medical applications point of view.