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One hundred and thirty SSR markers from wheat, maize and sorghum were screened for the transferability to Paspalum. The transfer rate was 67.5, 49.0 and 66.8% respectively. This would be a very efficient approach for DNA marker development for species which are not well studied molecularly. The polymorphism level for transferred SSR markers was 51.5% within species (Paspalum vaginatum) and 87.1% among Paspalum species. The high level of polymorphism is directly related to the high degree of heterozygosity maintained by its way of reproduction, i.e. self-incompatibility. Forty transferred polymorphic SSR markers were selected and used for characterization and evaluation of seventy-three Paspalum accessions. In total, 209 polymorphic bands were detected from these 40 SSR markers, with an average of five polymorphic bands per marker. The Paspalum accessions clustered into three major groups. Two very similar dendrograms can be generated from either 109 or 209 polymorphic bands. This led us to determine that 18 of the transferred SSR markers were sufficient for genetically differentiating the investigated germplasm accessions. The number of SSR markers required for germplasm characterization and evaluation is discussed. This is the first report of the transfer of SSR markers from major field crops to newly emerged environmental turfgrasses. [ABSTRACT FROM AUTHOR]

Photographs are used as a research tool by anthropologists and as a technique to empower special populations, advocacy groups, and policy makers. This case describes how photography was used to develop a survey to study alcohol expectancies among Thai adolescents. A multi-cultural research team faced generational, linguistic, and cultural barriers in understanding Thai adolescent alcohol use well enough to write useful questions about alcohol expectancies. Asking adolescents to take and then discuss their photographs about alcohol allowed them to express themselves without the imposition of an organizational framework by the investigators. Group discussions of the photographs revealed nuances and subtleties of interpretation of behavior and expectancies involving alcohol that might otherwise have not emerged. The results of this activity were used to refine an expectancy scale used in a large-scale survey of alcohol expectancies and use. [ABSTRACT FROM AUTHOR]

Corn stover is emerging as a viable feedstock for producing bioethanol from renewable resources. Dilute-acid pretreatment of corn stover can solubilize a significant portion of the hemicellulosic component and enhance the enzymatic digestibility of the remaining cellulose for fermentation into ethanol. In this study, dilute H2SO4 pretreatment of corn stover was performed in a steam explosion reactor at 160°C, 180°C, and 190°C, approx 1 wt % H2SO4, and 70-s to 840-s residence times. The combined severity (Log10 [Ro] - pH), an expression relating pH, temperature, and residence time of pretreatment, ranged from 1.8 to 2.4. Soluble xylose yields varied from 63 to 77% of theoretical from pretreatments of corn stover at 160 and 180°C. However, yields >90% of theoretical were found with dilute-acid pretreatments at 190°C. A narrower range of higher combined severities was required for pretreatment to obtain high soluble xylose yields when the moisture content of the acidimpregnated feedstock was increased from 55 to 63 wt%. Simultaneous saccharification and fermentation (SSF) of washed solids from corn stover pretreated at 190°C, using an enzyme loading of 15 filter paper units (FPU)/ g of cellulose, gave ethanol yields in excess of 85%. Similar SSF ethanol yields were found using washed solid residues from 160 and 180°C pretreatments at similar combined severities but required a higher enzyme loading of approx 25 FPU/g of cellulose. [ABSTRACT FROM AUTHOR]

In order to extend the investigation of the plasma cleaning of ITER first mirrors, a set of molybdenum mirrors was coated in a laboratory with ITER-relevant contaminants, namely beryllium and tungsten. Different coating techniques as well as several contaminant compositions were used to ensure a large variety of films to clean, completing a previous study conducted on mirrors exposed in the JET ITER-like wall (tokamak deposits) [1]. Due to the toxicity of beryllium, the samples were treated in a vacuum chamber specially built for this purpose. The cleaning was performed using capacitively coupled RF plasma and evaluated by performing reflectivity measurements, scanning electron microscopy, x-ray photoelectron spectroscopy and ion beam analysis. The removal of all types of contaminants was achieved by using different plasma compositions (argon, helium and mixtures of the two) with various ion energies (from 200–600 eV) and in some cases the mirror’s reflectivity was restored towards initial values. Pure helium discharges were capable of removing mixed beryllium/tungsten layers and oxidized molybdenum. In addition, no significant increase in the diffuse reflectivity of the mirrors was observed for the helium cleaning, though this was the case for some samples cleaned with argon. Helium is therefore appropriate for cleaning all mirrors in ITER leading to a possible cleaning regime where the entire vessel is filled with He and all mirrors are cleaned simultaneously without damaging their surfaces. [ABSTRACT FROM AUTHOR]

Previous reports have detailed the fabrication of media able to support high density magnetic recording in both longitudinal and perpendicular formats by the global rapid thermal processing of sputtered non-magnetic precursor films. During processing in this manner a magnetic element is released from its nitride and agglomerates to form a random near mono-dispersion of magnetic nano-particles. Here we explore, primarily through modelling and simulation, the feasibility of processing similarly formulated precursor media not globally but locally. We investigate the potential of using conducting nano-probe tips to produce, via electro-thermal (Joule) heating, a nano-patterned recording medium in the form of regular arrays of magnetic islands in a non-magnetic host. In the first instance we concentrate on the simplest cobalt based precursor medium for which both initial simulation and experimental studies indicate the formation of magnetic islands with dimensions of the order of the tip diameter; this is relatively straightforward. The results signify that if practical production scenarios can be devised to produce technologically significant areas of recording media by the rapid multi-probe repetition of this technique, then processing in this manner offers a promising route to areal recording densities of perhaps 5 Terabit/in2 even with the simplest cobalt media. We also note that the electro-thermal processing method is potentially extendable to the production of a wide variety of magnetic materials (e.g. PtCo, FeCo, NiFe alloys) and, applied via electrical nano-imprinting type techniques, to the production of a wide variety of patterned structures. [ABSTRACT FROM AUTHOR]

An abstract of the article "Spring Training in the Big Leagues: Making the Most of Your Team," by C. Bryan, L. Duncan et al. is presented.

The year-on-year growth in areal recording density maintained now for half a century by the hard disk industry has required a corresponding reduction in the size of the magnetic grains comprising the storage media employed. Grain dimensions are now such that the performance of materials which thus far have served the industry well can no longer be maintained as further reduction in their volume risks breaching the superparamagnetic limit with the attendant loss of data integrity. The high magnetocrystalline anisotropy of the Ll0 phase of PtCo allows particles as small as 4 nm diameter to remain magnetically stable in the elevated temperature environment typical of disk drive systems. A non-interacting dispersion of nanomagnetic particles suspended in an inert non-magnetic host such that each has its anisotropy axis directed perpendicular to the surface of the medium now constitutes the new ideal for a recording medium. Fabrication by a novel combination of conventional sputtering and thermal processing technologies of a medium closely approximating this ideal is demonstrated. An optimized two-stage fabrication process produces a near mono-dispersion of particles with magnetic activation volumes centred about 5 x 10[?]26 m[?]3 and crystallized in the L10 phase with an orientated tetragonal structure. The characteristics of this medium are discussed as a function of composition and crystalline structure. In the absence of a thermally assisted recording head, experiments are conducted on a degraded form of the medium that is shown to support perpendicular recording at linear densities in excess of 240 kfci (D50 point). [ABSTRACT FROM AUTHOR]