Analysis of 179 new Ebola virus sequences from patient samples collected in Guinea between March 2014 and January 2015 shows how different lineages evolved and spread in West Africa. Supplementary information The online version of this article (doi:10.1038/nature14594) contains supplementary material, which is available to authorized users.

A novel gas chromatograph-mass spectrometer (GC-MS) based on a miniature toroidal ion trap mass analyzer (TMS) and a low thermal mass GC is described. The TMS system has an effective mass/charge (m/z) range of 50-442 with mass resolution at full-width half-maximum (FWHM) of 0.55 at m/z 91 and 0.80 at m/z 222. A solid-phase microextraction (SPME) fiber mounted in a simple syringe-style holder is used for sample collection and introduction into a specially designed low thermal mass GC injection port. This portable GC-TMS system weighs <13 kg (28 lb), including batteries and helium carrier gas cartridge, and is totally self-contained within dimensions of 47 X 36 X 18 em (18.5 X 14 X 7 in.). System start-up takes about 3 min and sample analysis with library matching typically takes about 5 min, including time for column cool-down. Peak power consumption during sample analysis is about 80 W. Battery power and helium supply cartridges allow 50 and 100 consecutive analyses, respectively. Both can be easily replaced. An on-board library of target analytes is used to provide detection and identification of chemical compounds based on their characteristic retention times and mass spectra. The GC-TMS can detect 200 pg of methyl salicylate on-column. n-Butylbenzene and naphthalene can be detected at a concentration of 100 ppt in water from solid-phase microextraction (SPME) analysis of the headspace. The GC-TMS system has been designed to easily make measurements in a variety of complex and harsh environments. and toxic industrial chemicals (TICs), is a concern, the ability to rapidly detect and accurately identify such chemicals in harsh environments is of great utility. There is a need for field-portable, selective, and sensitive detectors for military and emergency first-responder operations and for on-site environmental contamination measurement, to mention only a couple of key applications. The development of fieldportable devices directed toward fast, on-site analysis is one of the most active research areas in analytical chemistry.Currently, several approaches for detection of CWAs and TICs are utilized by military personnel, first responders, and environmental scientists. They include dye solubility (detection paper), enzymatic reaction,

Electric field gradient focusing (EFGF) is a separation technique that uses an electric field gradient and an opposing hydrodynamic flow to separate and concentrate charged analytes. This work describes miniaturized EFGF devices that are used for protein analysis. These devices employ a unique ionically conductive polymer that enables the required electric field gradient to be established. This polymer has good protein compatibility and allows the transport of small buffer ions while retaining large analytes such as proteins. With the use of an EFGF device, green fluorescent protein was concentrated 10 000-fold and the separation of a protein mixture was demonstrated. The development of these ionically conductive polymer-based devices represents a step toward making EFGF a useful analytical tool for proteomics investigations.

We describe a novel radio frequency ion trap mass analyzer based on toroidal trapping geometry and microfabrication technology. The device, called the halo ion trap, consists of two parallel ceramic plates, the facing surfaces of which are imprinted with sets of concentric ring electrodes. Radii of the imprinted rings range from 5 to 12 mm, and the spacing between the plates is 4 mm. Unlike conventional ion traps, in which hyperbolic metal electrodes establish equipotential boundary conditions, electric fields in the halo ion trap are established by applying different radio frequency potentials to each ring. The potential on each ring can be independently optimized to provide the best trapping field. The halo ion trap features an open structure, allowing easy access for in situ ionization. The toroidal geometry provides a large trapping and analyzing volume, increasing the number of ions that can be stored and reducing the effects of space-charge on mass analysis. Preliminary mass spectra show resolution (m/Deltam) of 60-75 when the trap is operated at 1.9 MHz and 500 Vp-p.