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The conservation of Mayan wall paintings at the archaeological site of Calakmul (Mexico) will be one on the subjects touched upon by Piero Baglioni (based at the University of Florence) in his invited lecture at the 3rd European Chemistry Congress in Nürnberg in September. In a special issue of Chemistry-A European Journal, which contains papers by many of the speakers at this conference, he reports on the latest developments on the use of humble calcium and barium hydroxides nanoparticles as a versatile and highly efficient tool to combat the main degradation processes that affect wall paintings. La Antigua Ciudad Maya de Calakmul is located in the Campeche state (Mexico) and is one of the most important cities of the Classic Maya period (AD 250-800). The excavation of this site (set up in 1993) involves, under the supervision of the archaeologist Ramon Carrasco, archaeologists, architects, engineers, conservators and epigraphists, besides other specialists. Since 2004, the Center for Colloid and Surface Science (CSGI) at the University of Florence (CSGI), and currently directed by Piero Baglioni, has been an active partner, being involved in the study of the painting technique and in the development of nanotechnology for the consolidation and protection of the wall paintings and limestone.

The science behind gecko toes holds the answer to a dry adhesive that provides an ideal grip for robot feet. Stanford mechanical engineer Mark Cutkosky is using the new material, based on the structure of a gecko foot, to keep his robots climbing.

(Nanowerk News) Scientists at the University of Glasgow have devised a molecular 'LEGO toolkit' which can be used to assemble a vast number of new and functional chemical compounds. Using molecules as building blocks they have been able to construct a molecular scaffold based on tiny (nano-scale) storage cubes. This new ‘designer route’ opens the door to many new compounds that, potentially, are able to act as the ion sensors, storage devices, and catalysts of the future. Researchers within the Department of Chemistry created hollow cube-based frameworks from polyoxometalates (POMs) – complex compounds made from metal and oxygen atoms – which stick together like LEGO bricks meaning a whole range of well-defined architectures can be developed with great ease ("Face-directed self-assembly of an electronically active Archimedean polyoxometalate architecture").

Chemicals giant Merck KGaA (Darmstadt, Germany) and Plastic Logic GmbH (Dresden, Germany), the developer of the Que e-reader, have announced plans to develop, test and commercialize novel lisicon-type organic semiconductors from Merck in Plastic Logic's displays. The introduction and production of the materials is planned for 2011. Having shown the Que e-reader at the Consumer Electronics Show in January Plastic Logic was originally expected to ship the e-reader in April 2010 but that launch has now slipped to June, it is reported. Merck recently invested in the expansion of its Chilworth Technical Center chemicals research site in Southampton, England, by adding laboratories to intensify and accelerate display material developments based on plastic electronics.

"An industrial assembly line includes a factory, workers, and a conveyor system," said NYU Chemistry Professor Nadrian Seeman, the study's senior author. "We have emulated each of those features using DNA components." The assembly line relies on three DNA-based components. The first is DNA origami, a composition that uses a few hundred short DNA strands to direct a very long DNA strand to form structures to any desired shape. These shapes are approximately 100 x 100 nanometers in area, and about 2 nm thick (a nanometer is one billionth of a meter). DNA origami serves as the assembly line's framework and also houses its track. The second are three DNA machines, or cassettes, that serve as programmable cargo-donating devices. The cargo species the researchers used are gold nanoparticles, which measure 5 to 10 nanometers in diameter. Changing the cassette's control sequences allows the researchers to enable or prevent the donation of the cargoes to the growing construct. The third is a DNA "walker," which is analogous to the chassis of a car being assembled. It moves along the assembly line's track, stopping at the DNA machines to collect and carry the DNA "cargo." As the walker moves along the pathway prescribed by the origami tile track, it encounters sequentially the three DNA devices. These devices can be switched between an "on" state, allowing its cargo to be transferred to the walker, and an "off" state, in which no transfer occurs. In this way, the DNA product at the end of the assembly line may include cargo picked up from one, two, or three of the DNA machines. "A key feature of the assembly line is the programmability of the cargo-donating DNA machines, which allows the generation of eight different products," explained Seeman.