[en] Nine strains were identified to grow with gasoline as sole sulfur source. Two different genes were cloned from Gordonia terrae KGB1 and tested for the ability to support gasoline BDS. The first of these, fmoA, was cloned by screening a KGB1 gene library for the ability to convert indole to indigo (a sulfur-regulated capability in KGB1). The fmoA gene was overexpressed in a gasoline tolerant strain of Pseudomonas putida PpG1 and the recombinant strain was shown to convert thiophene to a dimer of thiophene sulfoxide at rates nearly two orders of magnitude higher than KGB1 could catalyze the reaction. Despite this high activity the recombinant PpG1 was unable to demonstrate any activity against gasoline either in shake flask or in bench-scale gasoline BDS bioreactor. A second gene (toeA) was cloned from KGB1 and shown to support growth of Rhodococcus erythropolis JB55 on gasoline. The toeA gene was also identified in another gasoline strain T. wratislaviensis EMT4, and was identified as a homolog of dszA from R. erythropolis IGTS8. Expression of this gene in JB55 supported conversion of DBTO2 (the natural substrate for DszA) to HPBS, but activity against gasoline was low and BDS results were inconsistent. It appeared that activity was directed against C2- and C3-thiophenes. Efforts to increase gene expression by plasmid manipulation, by addition of flavin reductase genes, or by expression in PpG1 were unsuccessful. The DszC protein (DBT monooxygenase) from IGTS8 has very little activity against the sulfur compounds in gasoline, but a mutant enzyme with a substitution of phenylalanine for valine at position 261 was shown to have an altered substrate range. This alteration resulted in increased activity against gasoline, with activity towards mainly C3- and C4-thiophenes and benzothiophene. A mutant library of dszB was constructed by RACHITT (W. C. Coco et al., DNA shuffling method for generating highly recombined genes and evolved enzymes. 2001. Nature Biotech. 19:354-359) method of in vitro recombination. Methods for analysis were developed and a preliminary analysis of the library was performed. A preliminary gasoline process design was constructed and process economics were determined based upon assumptions made from experimental results. The projected cost of gasoline BDS was determined to be competitive with current competing technologies

[en] Structure and function go hand in hand. However, while a complex structure can be relatively safely broken down into the minutest parts, and technology is now delving into nanoscales, the function of complex systems requires a completely different approach. Here the complexity clearly arises from nonlinear interactions, which prevents us from obtaining a realistic description of a system by dissecting it into its structural component parts. At best, the result of such investigations does not substantially add to our understanding or at worst it can even be misleading. Not surprisingly, the dynamics of complex systems, facilitated by increasing computational efficiency, is now readily tackled in the case of measured time series. Moreover, time series can now be collected in practically every branch of science and in any structural scale—from protein dynamics in a living cell to data collected in astrophysics or even via social networks. In searching for deterministic patterns in such data we are limited by the fact that no complex system in the real world is autonomous. Hence, as an alternative to the stochastic approach that is predominantly applied to data from inherently non-autonomous complex systems, theory and methods specifically tailored to non-autonomous systems are needed. Indeed, in the last decade we have faced a huge advance in mathematical methods, including the introduction of pullback attractors, as well as time series methods that cope with the most important characteristic of non-autonomous systems—their time-dependent behaviour. Here we review current methods for the analysis of non-autonomous dynamics including those for extracting properties of interactions and the direction of couplings. We illustrate each method by applying it to three sets of systems typical for chaotic, stochastic and non-autonomous behaviour. For the chaotic class we select the Lorenz system, for the stochastic the noise-forced Duffing system and for the non-autonomous the Poincaré oscillator with quasi-periodic forcing. In this way we not only discuss and review each method, but also present properties which help to clearly distinguish the three classes of systems when analysed in an inverse approach—from measured, or numerically generated data. In particular, this review provides a framework to tackle inverse problems in these areas and clearly distinguish non-autonomous dynamics from chaos or stochasticity

[en] Time series prediction has been applied to many business and scientific applications. Prominent among them are stock market prediction, weather forecasting, etc. Here, this technique has been applied to forecast plasma torch voltages to stabilize power using a backpropagation, a model of artificial neural network. The Extended-Delta-Bar-Delta algorithm is used to improve the convergence rate of the network and also to avoid local minima. Results from off-line data was quite promising to use in on-line

[en] The class of waste materials in the feedstream determines the treatment mechanism in a plasma torch waste vitrification environment. Artificial neural networks have been successfully applied to classification problems. In this study, five network architectures have been trained and tested to assess their performance for low level waste classification. Selected material properties constituted the input vectors for these networks. The training and test data sets were simulated based on the material and detector constraints. The Fuzzy ARTMAP proved superior to others tested, followed by counter propagation and learning vector quantization networks, for both full and restricted property sets. Validation with actual data is planned

[en] HTR-10, a proven 10 MWt prototype pebble bed reactor, is capable of generating 4 MWe to the power grid. However; with evolutional power upgrades, its output performance can be substantially enhanced to drive an energy complex to co-generate electricity, hydrogen, desalinated water and process heat for a remote island or settlement of several thousand people. Unlike the much publicized SMR power concepts in the literature, HTR-10 is the only full-blown stand-alone power system that has been demonstrated to be inherently safe and capable of high temperature output. Furthermore, this particular HTR family of reactors is proliferation-resistant and possesses many desirable market-competitive advantages such as high thermal efficiency, low thermal pollution, zero carbon footprints and minimal exclusion zones. An innovative classroom project course is structured to stimulate science and engineering students to explore novel use of HTR-10 as a high temperature heat source to be the core of an intelligent zero emission energy (Smart-ZEE) module capable of providing all energy needs of a remote community or island. (author)

[en] Highlights: • A new model for coupled solid-fluid problems is developed. • Solutions are found using a pure-Eulerian cell-centred Godunov method. • Interfaces are sharpened by using the THINC method. • Three dimensional simulations of cylinder impacts, and buried explosives are conducted. -- Abstract: In this paper a new three-dimensional Eulerian interface-capturing model is proposed for the simulation of compressible solid-fluid problems. The model is a development of a well-established five equation multi-fluid model to include material strength, by incorporating a new kinematic evolution equation for the elastic stretch tensor, and augmenting the Mie-Grüneisen equation-of-state to include a contribution from elastic strain. Principal to the development of the model is the fact that a great number of solid materials can be described by the particular general equation-of-state framework, which reduces to the Mie-Grüneisen equation-of-state in the limit of zero strength and is thus equally applicable to a wide class of fluids. The constitutive models are founded on hyperelastic theory and are therefore thermodynamically compatible. Only one kinematic equation is required for arbitrary numbers of components by assuming that mixtures are described by a common deviatoric strain tensor. The system of evolution equations can be written in conservation law form, and are therefore suitable for application of Godunov's method; specifically an HLLD Riemann solver is formulated for the calculation of numerical fluxes. Interfaces are sharpened by using the THINC method in conjunction with MUSCL reconstruction. A time operator splitting strategy is used to divide the time integration into an explicit elastic update, which uses the third order TVD Runge-Kutta method, followed by an implicit plastic update. The method is verified using a number of challenging solid-fluid problems, including a high-velocity impact of a viscoplastic strain-hardening cylinder in air. The potential of the model for practical problems is demonstrated through three-dimensional simulation of an explosive buried in solid ground material.

[en] The absorption and distribution of iodinated derivatives of nonoxynol-9, after vaginal administration in rats, were compared with results reported for [¹⁴C] nonoxynol-9. Mono-iodinated nonoxynol-9 was synthesized in addition to the radiolabeled derivative incorporating iodide-125 ([¹²⁵I]). Six hours after dosing, test rats were euthanized and selected tissues were excised and assessed for radioactivity. Levels of radioactive markers in the reproductive system were substantial for both [¹⁴C] and [¹²⁵I]. It was concluded that [¹²⁵I] mono-iodinated nonoxynol-9 and [¹⁴C] nonoxynol-9 possessed similar bioavailability

[en] The West Valley melter has been taken out of service. Its design is the direct ancestor of the current melter design for the Hanford Waste Treatment Plant. Over its eight years of service, the West Valley melter has endured many of the same challenges that the Hanford melter will encounter with feeds that are similar to many of the Hanford double shell tank wastes. Thus, inspection of the West Valley melter prior to its disposal could provide valuable--even crucial--information to the designers of the melters to be used at the Hanford Site, particularly if quantitative information can be obtained. The objective of Mississippi State University's Diagnostic Instrumentation and Analysis Laboratory's (DIAL) efforts is to develop, fabricate, and deploy inspection tools for the West Valley melter that will (i) be remotely operable in the West Valley process cell; (ii) provide quantitative information on melter refractory wear and deposits on the refractory; and (iii) indicate areas of heterogeneity (e.g., deposits) requiring more detailed characterization. A collaborative arrangement has been established with the West Valley Demonstration Project (WVDP) to inspect their melter

[en] This trial was accomplished in C3H mice to determine whether hyperbaric oxygen (HBO) could be administered to prevent delayed radiation enteropathy. Fifty mice randomized into two equal groups received 30 Gy abdominopelvic irradiation in 10 fractions. The study group received a course of 30 HBO treatments beginning 7 weeks after the radiation exposure. The control group received only housing and nutritional support after irradiation. A third group of three animals had no radiation or HBO. All animals were sacrificed 7 months after radiation. Animals were inspected grossly for signs of enteropathy. In addition, a special stretch apparatus was used to quantify narrowing and rigidity of ileum just proximal to the ileocecal junction. Those animals who received HBO had fewer gross signs of enteropathy and had less narrowing and less rigidity in their harvested bowel segments. These differences were highly statistically significant. Treatment with HBO drastically reduces signs of radiation enteropathy. Further study including clinical trials are recommended

[en] The San Mateo Creek Basin in New Mexico, USA is located within the Grants Mineral Belt-an area with numerous uranium (U) ore deposits, mines, and milling operations. Six monitoring wells set in an alluvial aquifer near the Homestake Mining Co. Superfund site in the lower San Mateo Creek Basin were logged with a suite of borehole geophysical tools including spectral gamma-ray (SGR), vertically profiled with passive samplers for U and selenium (Se) concentrations, and purged sampled for same constituents. The integrated approach allowed for an assessment on the role of heterogeneity (both physical and chemical) in determining U concentrations in groundwater. Uranium, as measured with SGR logging, is ubiquitous in the alluvial aquifer and the underlying Chinle Group. Aqueous U concentrations appear to be inversely related to thorium (Th) concentrations, as measured by the SGR log, indicating the possibility that U is bound in or adsorbed to clays in the aquifer. The stratigraphy of the alluvium likely plays a role in elevated concentrations of aqueous U. Interbedded clay and sand layers allow for the mobilization of U in oxic sandy layers from U adsorbed in sediments in reduced clay layers. The stratigraphy also plays a role in the degree of mixing of groundwater in the formation and well. Mixing can obscure the ability to identify U sources. Mixing is exacerbated by the relatively long screens (> 20 ft long or > 6.1 m) of the monitoring wells.