Evaluation of several modifications of an ecometric technique for assessment of media performance

Recovery of Listeria monocytogenes 101M, Jonesia denitrificans, salmonellae, and Pediococcus sp. NRRL B-2354 across nine media was evaluated with three modified versions of an ecometric method. Two approaches involved the use of broth cultures (10(8) to 10(9) CFU/ml) of individual strains and either large (10-microl) or small (1-microl) presterilized plastic loops. The third approach involved precultured slants and the inoculation of media with presterilized plastic inoculating needles (10(4) CFU per needle). Absolute growth indices (AGIs) were compared. No significant differences (P < 0.05) between methods were found when tryptic soy agar supplemented with 0.6% yeast extract (TSAYE) was used for the recovery of L. monocytogenes, J. denitrificans, Pediococcus sp. NRRL B-2354, and Salmonella spp. However, the small loop-broth technique recovered significantly fewer Salmonella enterica Typhimurium DT104 and Salmonella Senftenberg 775W cells than the other two techniques did. The performance of each individual bacterial strain on each of nine media was assayed. The recovery of L. monocytogenes was excellent (AGI > 4.8) with TSAYE, PALCAM, modified Oxford medium (MOX), and Baird-Parker agar and slight with modified PRAB (AGI = 0.4) and deMan Rogosa Sharpe (MRS) agar (< 0.1), and the organism was not recovered with the remaining media (modified lysine iron agar [MLIA], xylose lysine desoxycholate [XLD] agar, and xylose lysine tergitol 4 [XLT4] agar). The recovery of J. denitrificans with TSAYE and MOX was excellent, significantly better than that achieved with PALCAM (AGI = 3.0), but the organism was not recovered with Baird-Parker agar or with the other media tested. The recovery of Pediococcus sp. NRRL B-2354 was excellent with TSAYE and modified PRAB medium > Baird-Parker agar > acidified MRS agar, but the organism was not recovered with any of the other media tested. The best recovery of S. enterica Typhimurium DT104 was achieved with TSAYE > MLIA > or = XLD agar > or = XLT4 agar > Baird-Parker > PALCAM, MOX, acidified MRS agar, modified PRAB, and MRS agar. The best recovery of Salmonella Senftenberg 775W was achieved with TSAYE, MLIA, and XLD agar > XLT4 agar, but the organism was not recovered with the other media evaluated.     

Numerical modeling of a non-flooding hybrid polymer electrolyte fuel cell

Experimental results were recently reported regarding a novel “non-flooding” hybrid fuel cell consisting of proton exchange membrane (PEM) and anion exchange membrane (AEM) half-cells on opposite sides of a water-filled, porous intermediate layer. Product water formed in the porous layer, where it could permeate to the exterior of the cell, rather than at the electrodes. Although electrode flooding was mitigated, the reported power output was low. To investigate the potential for increased power output, a physicochemical charge transport model of the porous electrolyte layer is reported here. Traditional electrochemical modeling was generalized in a novel way to consider both ion transport and reaction in the aqueous phase and electronic conduction in the graphitic scaffold using a unified Poisson–Nernst–Planck framework. Though the model used no arbitrary or fitting parameters, the ionic resistance calculated for the porous layer agreed well with the highly non-Ohmic experimental values previously reported for the entire fuel cell. Interestingly, electronic charge carriers in the scaffold were found to obviate the need for counterion presence in this unique electrolyte structure. Still, the thickness- and temperature-dependent model results offer limited prospects for improving the power output.     

Development and application of a real-time water environment cyberinfrastructure for kayaker safety in the Apostle Islands,Lake Superior

Assessing all pertinent environmental variables to categorize a skill level to safely navigate the water environment can be difficult for inexperienced kayakers, especially at a remote site where internet access is limited. A real-time kayaker safety assessment of water environmental conditions at the Mainland Sea Caves of the Apostle Islands National Lakeshore, Lake Superior is achieved. We present a new cyberinfrastructure that provides kayakers with real-time data access and a Safety Index (SI) with consideration of multiple environmental factors to characterize the degree of navigational difficulty for classifying kayaker skill levels. Specifically, radar reflectivity is added to improve forecasts of dangerous conditions caused by convective storms using state-of-the-art weather and wave modeling. Spectral characteristics of surface waves are employed to correlate the occurrences of extreme and freak waves. In addition, unexpectedly dangerous conditions like coastal upwelling and freak wave occurrence due to changing wind directions are considered. A contingency plan is implemented to handle the issue of possibly missing required environmental data. Display of the SI and visualization of other real-time environmental data are communicated by a power-efficient kiosk. Web analytics demonstrates a public interest in real-time water conditions and the need for the on-site kiosk to provide the latest information before kayakers enter the water. The new real-time water environment cyberinfrastructure for kayaker safety in the Apostle Islands, Lake Superior has been successfully operated since 2014.     

Does willingness to pay for green energy differ by source?

We present the findings of a choice experiment designed to estimate consumer preferences and willingness-to-pay (WTP) for voluntary participation in green energy electricity programs. Our model estimates WTP for a generic “green energy” source and compares it to WTP for green energy from specific sources, including wind, solar, farm methane, and biomass. Our results show that there exists a positive WTP for green energy electricity. Further, individuals have a preference for solar over a generic green and wind. Biomass and farm methane are found to be the least preferred sources.     

Optimized excitation energy transfer in a three-dye luminescent solar concentrator

The spectral range of sunlight absorbed by a luminescent solar concentrator (LSC) is increased by using multiple dyes. Absorption, fluorescence, and fluorescence excitation spectra, and relative light output are reported for LSCs made with one, two, or three BODIPY dyes in a thin polymer layer on glass. Losses caused by multiple emission and reabsorption events are minimized by optimizing resonance excitation energy transfer between dyes. Increases in the outputs from the multiple-dye LSCs are directly proportional to increases in the number of photons absorbed. The output of the three-dye LSC is 45–170% higher than those of the single-dye LSCs.     

Crystalline silicon surface passivation by amorphous silicon carbide films

This article reviews the surface passivation of n- and p-type crystalline silicon by hydrogenated amorphous silicon carbide films, which provide surface recombination velocities in the range of 10 cm s⁻¹. Films are deposited by plasma-enhanced chemical vapor deposition from a silane/methane plasma. We determine the passivation quality measuring the injection level (Δn)-dependent lifetime (τ_eff(Δn)) by the quasi-steady-state photoconductance technique. We analyze the experimental τ_eff(Δn)-curves using a physical model based on an insulator/semiconductor structure and an automatic fitting routine to calculate physical parameters like the fundamental recombination velocities of electrons and holes and the fixed charge created in the film. In this way, we get a deeper insight into the effect of the deposition temperature, the gas flow ratio, the doping density of the substrate and the film thickness on surface passivation quality.     

Immunoreactive fraction 1 leaf protein and dry matter content during wilting and ensiling of ryegrass and alfalfa

In four experiments with ryegrass and alfalfa, cut herbage was wilted in the field and silage made in 1- or 200-L silos. Direct-cut (mean DM, 20.3%), low wilt (mean DM, 26.0%), medium wilt (mean DM, 36.2%) and high wilt (mean DM, 47.7%) herbages were used. Fraction 1, the most abundant leaf protein, was measured by crossed immunoelectrophoresis using rabbit anti-Fraction 1 serum. In two ryegrass and one alfalfa experiments in which weather conditions allowed rapid drying to high wilt herbage in 24 h, there was no significant loss of Fraction 1 protein. In the second alfalfa experiment, in which wilting was prolonged to 3 d by adverse weather, there was a 70% loss of Fraction 1. Ensiling proceeded normally in the four experiments, with rapid fall in pH and production of VFA, lactate, and NPN; the extent and rates of production were inversely related to DM content. In alfalfa and ryegrass, pH fell below the isoelectric point of Fraction 1 within 8 d. In each ryegrass experiment, a high proportion (58 to 100%) of Fraction 1 in medium and high wilt silages survived fermentation for 28 and 68 d, with lesser amounts in other silages. With alfalfa, however, almost all Fraction 1 protein was degraded at all DM concentrations during fermentation. Fiber-associated protein increased markedly with increases in DM during wilting, and these differences were present in the mature silage of both ryegrass and alfalfa. Digestibility studies with fistulated sheep showed that appreciable amounts of immunoreactive Fraction 1 protein in ryegrass silages were undegraded in the rumen.     

A randomized,double-blind trial on the bioavailability of two CoQ10 formulations

The bioavailability of a single, 100 mg, dose of reduced Coenzyme Q10 (CoQH-CF) and Coenzyme Q10 formulation was compared in individuals of >60 years. Significantly higher (P < 0.001) plasma concentrations were demonstrated for the CoQH-CF formulation at 5, 6, 8, 12, 24, 48 and 72 h post-dose compared to the CoQ10 formulation. The area under the curve (AUC) of reduced and total Coenzyme Q10 was significantly higher (P < 0.001) in subjects administered CoQH-CF resulting in 4.3-fold higher plasma AUC_{0–72 h} (430% increase) in subjects receiving CoQH-CF compared to subjects receiving Coenzyme Q10. Oxidized Coenzyme Q10 in plasma was higher (P < 0.001) in subjects receiving CoQH-CF compared to subjects receiving Coenzyme Q10 resulting in a 3.3-fold higher plasma AUC_{0–72 h} (329% increase). Total CoQ10 reached maximum plasma concentrations 15.5 ± 19.6 h after supplementation with CoQH-CF and 26.5 ± 25.8 h after supplementation with Coenzyme Q10, respectively. Thus, reduced Coenzyme Q10 liquid soft gel formulation was found to be superior to the commercial formulation of Coenzyme Q10 for bioavailability.     

Similarity and assumed similarity in personality reports of well-acquainted persons.

The authors obtained self- and observer reports of personality from pairs of well-acquainted college students. Consistent with previous findings, results of Study 1 showed strong cross-source agreement for all 6 HEXACO personality factors (rs ≈ .55). In addition, the authors found modest levels of similarity (r ≈ .25) between dyad members' self-reports on each of 2 dimensions, Honesty-Humility and Openness to Experience. For these same 2 factors, dyad members' self-reports were correlated with their observer reports of the other dyad member (r ≈ .40), thus indicating moderately high assumed similarity. In Study 2, Honesty-Humility and Openness to Experience were the 2 personality factors most strongly associated with the 2 major dimensions of personal values, which also showed substantial assumed similarity. In Study 3, assumed similarity was considerably stronger for close friends than for nonfriend acquaintances. Results suggest that assumed similarity for Honesty-Humility and Openness to Experience reflects a tendency to overestimate one's similarity to persons with whom one has a close relationship, but only on those personality characteristics whose relevance to values gives them central importance to one's identity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)