This is a partial listing of science news items from the SpectroscopyNOW archives
from 2001-2005.
Crystalline imaging
Scientists
in the US have demonstrated a new technique that can follow the
crystallisation process from the very first seeding and provide a sequence
of real time images. The technique could open up new avenues of
investigation into crystal structure, perhaps lead to new ways to make
novel crystalline solid, and even allow researchers to develop ways to
crystallise previously intractable materials for subsequent
crystallographic studies.
Crystalline cancer drug
After ten years of work on the novel anticancer drug epothilone, researchers finally obtained a crystal structure of it its bioactive conformation bound to the cellular component tubulin in 2004. Now, the compound's discoverer discusses the implications of the structure and the future of epothilone.
Carbon's liquid assets
A collaboration between US and Swiss researchers has provided new insights into the nature and bonding of carbon in the liquid phase. The team exploited a newly developed technique, picosecond time-resolved X-ray absorption spectroscopy, which allows them to overcome problems of liquid carbon's high volatility and its transient nature.
Chagas crystallised
The crystal structure of the tryparedoxin peroxidase from the human parasite Trypanosoma cruzi which causes the lethal South American trypanosomiasis known as chagas is reported for the first time by researchers in Uruguay and France. The structure will improve our understanding of metabolic processes in tripanosomes and could provide a new target for drugs against the disease.
Resonants - Issue 18 of the NMR news webzine is out now Cockroach cocktailUS chemists have used NMR to identify the active component of the sex attractant of the female cockroach. Having now also synthesised the compound for the first time, they suggest it could become a new tool for fighting this common urban pest, which would beat the shoe heel and reduce the need for widespread insecticidal spraying.
Molecular apple peelA helical molecule that wraps itself around a smaller compound in a fashion resembling an apple peel encapsulating an egg can isolate its captive from solvent molecules. NMR studies by the inventors of the molecular apple peel reveal that the system could represent an entirely new approach to making supramolecular host-guest structures for catalysis, sensors, and reactions.
Superconducting wiresUS researchers have discovered that ultrathin superconducting wires can withstand stronger magnetic fields than larger wires composed of the same material and could be useful in NMR and MRI technologies.
CASSINI-HUYGENS SPECIAL ISSUE - Spectral Lines Issue 44 The mission An astounding vision of raging winds, a methane-rich atmosphere and a surface of dirty ice frozen like rock is emerging from data transmitted the billion and a half kilometres to Earth. The instruments aboard the Huygens probe, which plunged into the atmosphere of Titan the largest of Saturn's 33 moons on January 14 are painting a picture of an enigmatic atmosphere and complex surface chemistry that will keep the scientist involved in the project busy for years. A Titanic methane source The Aerosol Collector and Pyrolyser aboard Huygens collected atmospheric aerosols carried out a preparation involving evaporation, pyrolysis and gas product transfer and then an analysis with gas chromatography-mass spectrometry. The ACP collected two samples one from the top of the descent down to the tropopause and the second sample in the cloud layer. Descend and detect Huygen's Descent Imager/Spectral Radiometer took images of Titan's surface as well as making spectroscopic measurements over a wide spectral range. DISR surface images revealed the region of Titan on which the probe landed to have a pebbly and dry riverbed while the colour spectral measurements were shown to be consistent with a composition of dirty water ice rather than silicate rocks. At Titan's chilling temperatures though this material has rock-like properties rather than behaving like water ice on Earth. Crème Brulée and surface science It was the Huygens Atmosphere Structure Instrument that allowed Huygens to tell researchers that the surface at the point of impact is rather like "crème brulée" having a hard skin but a squelchy interior. Huygens' Surface Science Package is a suite of sensors to determine the physical properties of the surface at the impact site and to provide unique information about its composition. Doppler results - no small breeze The Doppler Wind Experiment used radio signals to deduce atmospheric properties. The probe drift caused by winds in Titan's atmosphere produced a measurable Doppler shift in the carrier signal to be relayed to the Cassini Orbiter by Huygens. The swinging motion of the probe beneath its parachute and other radio-signal-perturbing effects, such as atmospheric attenuation, would also be detectable from the signal. RESONANTS Crystal gas tankSounding out dolphin navigation with NMR
Italian researchers have used NMR and morphological studies to determine the lipid composition of the "melon", the echolocation organ of the striped dolphin. Their findings might ultimately lead to a new approach to tuna fishing in the Mediterranean that prevents the species from being needlessly trapped in fishing nets.
NMR relates metabolic syndrome to ethnicity A proton NMR study has found that almost one third of American adults in a large urban population sample have fatty liver disease, hepatic steatosis, and has shed some light on the link between ethnicity and the disease. Spinning a yarnChinese researchers have developed a new type of artificial fibre that could side-step the pollutant issues associated with the production of viscose. The team used wide angle X-ray diffraction and CP/MAS carbon NMR to show that their novel cellulose fibres have a structure typical for a family II cellulose and possess a relatively high degree of crystallinity.
Toxic imprint A polymer imprinted with the three-dimensional shape of bisphenol A-d16 will be useful in detecting bisphenol A in blood serum and allow more accurate monitoring of people working in the polymer resin industry as well as those suspected of environmental exposure. Reversible aggregationUV/Vis spectroscopy reveals how gold nanoparticles can be reversibly bound to DNA, opening up a new inroad to the research field of bionanotechnology.
Martian blueberries NASA's Opportunity rover is currently wending its way across the Martian landscape sampling and testing in the hope of finding nuggets of information that will improve our understanding of the Red Planet and even provide evidence of water and so the possibility of life there. Opportunity's Mössbauer spectrometer specifically identifies iron-containing rocks and at the beginning of December identified four mineralogic components in Meridiani Planum at Eagle crater, including haematite-rich "blueberries" and jarosite, an iron hydroxide sulfate mineral. Electron channels An Austrian team has used photoelectron spectroscopy and other techniques to observe for the first time the details of electrons as they move along predetermined channels in a metal. The research provides important new insights into the interactions of electrons and could have implications for the development of new superconducting materials.In the latest issue of X-factors: Japanese researchers have used X-ray diffraction to show how silicon nitride ceramics crystallise in a strong magnetic field. Their findings reveal that the magnetic field can reorient the crystal lattice and so could provide an effective way of fine-tuning the physical properties of these important technological materials. Red wine connoisseurs will be pleased to learn that the crystal structure and ab initio calculations of the phenolic antioxidant resveratrol found in their favourite tipple both reveal a structure that might explain the compound's potent antioxidant properties and its purported protective effects on the heart.
Finding a way to arrange nanowires on a surface will be crucial to their development as useful materials for future molecular electronics and other nanoscale devices. Now, an Israeli team has demonstrated that single-walled carbon nanotube patterns can be produced using atomic steps on such a surface as a template. They have also devised a new technique, "asymmetric double-exposure back-reflection XRD", to help them determine the surface characteristics. Highlighted this month in Spectral Lines: Smart dust goes magnetic - Dust-sized chips of silicon can surround and control the motion of molecules, cells, and bacteria within a droplet of liquid, according to chemists at the University of California, San Diego. Also in Issue 41, Titan's electronic secrets, UK astronomers take a spectral view of Saturn's major moon, weight gain revelations, and finally, the infra-red miner's lamp.