1,105 research outputs found
The adsorption of environmental pollutants in gas and aqueous media utilizing nano-scale materials
In this body of work, the synthesis and characterization of several nanoporous materials have been described, as well as the application of these materials towards environmentally positive means. Largely, this work involves porous carbon materials produced from the amino acid L-histidine, a porous carbon precursor high in nitrogen and oxygen. Although pyrolysis of this precursor alone produces a non-porous foam, the introduction of any of a number of activating agents is shown here to produce a variety of amorphous and highly porous carbon materials. While applications of these materials have a very wide range, in this body of work the adsorption of pollutants is emphasized. Among the aqueous pollutants, both textile dyes and pharmaceuticals were investigated for their abilities to be taken up by these porous carbon materials. Individually, many of the porous carbons were capable of the uptake of noteworthy quantities of various pollutants. Yet, a broader finding in this work was that it appears the ‘tuning' of properties on a porous carbon is required to target each different adsorbate; no single property is universally linked to higher capacities. Apart from aqueous pollutants, the adsorption of CO2 was thoroughly investigated on many porous carbons. Given their high nitrogen content, it was expected that these materials would do well for CO2 uptake. And indeed, it was found that several histidinederived porous carbons were capable of noteworthy capacities, such as 8.30 and 5.57 mmol g-1. Through investigation of the porous carbon textural and chemical properties, these capacities are ascribed to a mixture of physisorption and chemisorption processes. Finally, the adsorption of CO2 was investigated on an amine-coated porous silica. With the purpose of making such nano-scale materials more feasible, immobilization inside a bacterial cellulose framework is investigated. Ultimately, it was found that after finetuning the loading process, a functional hybrid material can be made that successfully immobilizes the adsorbent material without sacrificing the capture abilities
Combinatorial structures in loops
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46265/1/209_2005_Article_BF01221880.pd
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Coccidioidomycosis Complement Fixation Titer Trends in the Age of Antifungals.
Coccidioidomycosis is associated with a broad spectrum of illness severity, ranging from asymptomatic or self-limited pulmonary infection to life-threatening manifestations of disseminated disease. Serologic studies before the widespread availability of antifungals established current understanding of serologic kinetics and dynamics. Chart histories and complement fixation (CF) titer trends were analyzed for 434 antifungal-treated coccidioidomycosis patients, who were classified by three infectious disease physicians as having either pulmonary uncomplicated coccidioidomycosis (PUC) (n = 248), pulmonary chronic coccidioidomycosis (PCC) (n = 64), disseminated coccidioidomycosis (DC) not including meningitis (n = 86), or coccidioidal meningitis (CM) (n = 36). The median maximal CF titers were 1:4 for PUC patients, 1:24 for PCC patients, 1:128 for DC patients, and 1:32 for CM patients. Approximately 25.4% of PUC patients, 6.2% of PCC patients, 2.3% of DC patients, and 8.3% of CM patients did not develop detectable titers during the study period. Maximal titers developed a mean of 31 days (95% confidence interval [CI], 13 to 50 days) after initial serologic positivity, with no significant differences between groups. Serologic recurrence occurred in 9% of PUC patients, 36% of PCC patients, 50% of DC patients, and 52% of CM patients. Median titer improvement rates were 91 days/dilution for PUC patients, 112 days/dilution for PCC patients, 136 days/dilution for DC patients, and 146 days/dilution for CM patients. Receiver operating characteristic (ROC) analysis revealed that CF testing retains moderate classification value for disseminated infections (area under the curve [AUC], 0.82 [95% CI, 0.78 to 0.87]) and complicated infections (AUC, 0.82 [95% CI, 0.77 to 0.86]). A suitable cutoff value for complicated infections is ≥1:32. Findings update serologic parameters that are relevant for clinical assessment of coccidioidomycosis patients in the triazole era
A Two-Player Game of Life
We present a new extension of Conway's game of life for two players, which we
call p2life. P2life allows one of two types of token, black or white, to
inhabit a cell, and adds competitive elements into the birth and survival rules
of the original game. We solve the mean-field equation for p2life and determine
by simulation that the asymptotic density of p2life approaches 0.0362.Comment: 7 pages, 3 figure
Search for active-sterile neutrino mixing using neutral-current interactions in NOvA
We report results from the first search for sterile neutrinos mixing with active neutrinos through a reduction in the rate of neutral-current interactions over a baseline of 810 km between the NOvA detectors. Analyzing a 14-kton detector equivalent exposure of 6.05×10^(20) protons-on-target in the NuMI beam at Fermilab, we observe 95 neutral-current candidates at the Far Detector compared with 83.5 ± 9.7(stat) ± 9.4(syst) events predicted assuming mixing only occurs between active neutrino species. No evidence for ν_μ→ν_s transitions is found. Interpreting these results within a 3+1 model, we place constraints on the mixing angles θ_(24) < 20.8° and θ_(34_ < 31.2° at the 90% C.L. for 0.05 eV^2 ≤ Δm^2_(41) ≤ 0.5 eV2, the range of mass splittings that produce no significant oscillations over the Near Detector baseline
Contralateral manual compensation for velocity-dependent force perturbations
It is not yet clear how the temporal structure of a voluntary action is coded allowing coordinated bimanual responses. This study focuses on the adaptation to and compensation for a force profile presented to one stationary arm which is proportional to the velocity of the other moving arm. We hypothesised that subjects would exhibit predictive coordinative responses which would co-vary with the state of the moving arm. Our null hypothesis is that they develop a time-dependent template of forces appropriate to compensate for the imposed perturbation. Subjects were trained to make 500 ms duration reaching movements with their dominant right arm to a visual target. A force generated with a robotic arm that was proportional to the velocity of the moving arm and perpendicular to movement direction acted on their stationary left hand, either at the same time as the movement or delayed by 250 or 500 ms. Subjects rapidly learnt to minimise the final end-point error. In the delay conditions, the left hand moved in advance of the onset of the perturbing force. In test conditions with faster or slower movement of the right hand, the predictive actions of the left hand co-varied with movement speed. Compensation for movement-related forces appeared to be predictive but not based on an accurate force profile that was equal and opposite to the imposed perturbatio
Localization dynamics in a binary two-dimensional cellular automaton: the Diffusion Rule
We study a two-dimensional cellular automaton (CA), called Diffusion Rule
(DR), which exhibits diffusion-like dynamics of propagating patterns. In
computational experiments we discover a wide range of mobile and stationary
localizations (gliders, oscillators, glider guns, puffer trains, etc), analyze
spatio-temporal dynamics of collisions between localizations, and discuss
possible applications in unconventional computing.Comment: Accepted to Journal of Cellular Automat
Constraints on Oscillation Parameters from ν_e Appearance and ν_μ Disappearance in NOvA
Results are reported from an improved measurement of ν_μ→ν_e transitions by the NOvA experiment. Using an exposure equivalent to 6.05×10^(20) protons on target, 33 ν_e candidates are observed with a background of 8.2±0.8 (syst.). Combined with the latest NOvA ν_μ disappearance data and external constraints from reactor experiments on sin^2 2θ_(13), the hypothesis of inverted mass hierarchy with θ_(23) in the lower octant is disfavored at greater than 93% C.L. for all values of δ_(CP)
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Evaluation of Homogeneous Options: Effects of Minor Actinide Exclusion from Single and Double Tier Recycle in Sodium Fast Reactors
The Systems Analysis Campaign under the Global Nuclear Energy Partnership (GNEP) has requested the fuel cycle analysis group at the Idaho National Laboratory (INL) to analyze and provide isotopic data for four scenarios in which different strategies for Minor Actinides (MA) management are investigated. A 1000 MWth commercial-scale Sodium Fast Reactor (SFR) design was selected as the baseline in this scenario study. Two transuranic (TRU) conversion ratios, defined as the ratio of the amount of TRU produced over the TRU destroyed in the reactor core, along with different fuel-types were investigated
Asymmetric interlimb transfer of concurrent adaptation to opposing dynamic forces
Interlimb transfer of a novel dynamic force has been well documented. It has also been shown that unimanual adaptation to opposing novel environments is possible if they are associated with different workspaces. The main aim of this study was to test if adaptation to opposing velocity dependent viscous forces with one arm could improve the initial performance of the other arm. The study also examined whether this interlimb transfer occurred across an extrinsic, spatial, coordinative system or an intrinsic, joint based, coordinative system. Subjects initially adapted to opposing viscous forces separated by target location. Our measure of performance was the correlation between the speed profiles of each movement within a force condition and an ‘average’ trajectory within null force conditions. Adaptation to the opposing forces was seen during initial acquisition with a significantly improved coefficient in epoch eight compared to epoch one. We then tested interlimb transfer from the dominant to non-dominant arm (D → ND) and vice-versa (ND → D) across either an extrinsic or intrinsic coordinative system. Interlimb transfer was only seen from the dominant to the non-dominant limb across an intrinsic coordinative system. These results support previous studies involving adaptation to a single dynamic force but also indicate that interlimb transfer of multiple opposing states is possible. This suggests that the information available at the level of representation allowing interlimb transfer can be more intricate than a general movement goal or a single perceived directional error
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