Comparison of five selective media for identifying fecal carriage of vancomycin-resistant enterococci

There is no uniformly accepted method for detecting colonization with vancomycin-resistant enterococci (VRE). The sensitivities of five culture methods were determined for patients known to harbor VRE. Of 189 inpatients, 101 were found to harbor VRE by at least one method. Three methods detected fewer than half of the cultures. Campylobacter agar identified 70% of patients. Enterococcosel broth (containing vancomycin and aztreonam) identified 88% and may be preferred over other media for routine surveillance.     

STEADY SHEAR FLOW PROPERTIES OF HIGH SOLIDS SOFTWOOD KRAFT BLACK LIQUORS: EFFECTS OF TEMPERATURE, SOLIDS CONCENTRATIONS, LIGNIN MOLECULAR WEIGHT AND SHEAR RATE

The steady shear flow properties of several softwood kraft black liquors (slash pine) from a two level, four variable factorially designed pulping experiment were determined for solids concentrations from 50% to 85%, temperatures from 40°C to 140°C and shear rates up to 10,000 s-1 by using Instron capillary and Haake coaxial cylinder rheometers. It was shown that the slip velocity at the wall of the capillary is insignificant and that a two capillary method can be used to determine the viscosity of the samples. At high solids, black liquor can exhibit non-Newtonian behavior dependent upon temperature, solids concentrations, solids composition and shear rate. In general, the liquors behave as pseudoplastic fluids. The exact level of viscosity at any given condition is dependent upon the solids composition which will vary from liquor-to-liquor. The flow behavior of the liquors was described using power-law, Cross and Carreau-Yasuda models. Superposition principles developed for polymer melts and concentrated polymer solutions were applied to obtain reduced correlations for viscosity behavior of the liquors. By using a suitable reference temperature, related to the glass transition temperature of black liquors, a generalized WLF type shift factor was obtained for the liquors used in this study and can be used to obtain a reduced plot of viscosity behavior of other black liquors.     

Mitomycin C induced alterations in antioxidant enzyme levels in a model insect species, Spodoptera eridania

1. An insect species, the southern armyworm Spodoptera eridania, was used as an in vivo model to examine mitomycin C's (MMC) pro-oxidant effect reflected in alterations of antioxidant enzymes. 2. Following a 2-day exposure to 0.01 and 0.05% w/w dietary concentrations, MMC only induced superoxide dismutase activity. All other enzyme activities were not affected, indicating oxidative stress was mild. 3. Following a 5-day exposure to 0.05% w/w dietary MMC, the activities of superoxide dismutase, glutathione-S-transferase and its peroxidase activity and DT-diaphorase were induced. GR activity was not altered. The high constitutive catalase activity was also not affected. These responses of S. eridania's antioxidant enzymes are analogous to those of mammalian systems in alleviating MMC-induced oxidative stress. 4. S. eridania emerges as an appropriate non-mammalian model for initial and cost-effective screening of drug-induced oxidative stress.     

The impedance of a single-turn coil near a conducting half space

The change in complex impedance between an ideal one-turn circular coil located above and parallel to a conducting half space with respect to a similar isolated coil has been calculated. From this result, a series expansion of the integrand allows the solution to be approximated by terms expressed as complete elliptic integrals. Results have been calculated for the change in impedance as a function of the liftoff distance and the conductivity of the half space for a coil of representative radius.     

Dual polarised microstrip patch antenna with high port isolation

A probe fed stacked microstrip patch antenna for operation in dual polarisation mode is proposed. A slot loaded lower patch is presented to improve isolation between the two polarisation ports. Simulations and measurements show two linear polarisations with an isolation of more than 30 dB within the band 2.5-2.7 GHz. A return loss of -10 dB is achieved within the above-mentioned bandwidth for the proposed antenna. The radiation pattern for the antenna is similar to that of a conventional microstrip antenna and the measured cross-polar level is 16.5 dB below the peak co-polar level within the band 2.5-2.7 GHz     

Trigate FET Device Characteristics Improvement Using a Hydrogen Anneal Process With a Novel Hard Mask Approach

It is reported that hydrogen anneal after fin formation improves the multigate MOSFET I_on/I_off ratio. However, a higher anneal temperature also results in silicon loss from the fins, thereby reducing the effective width of the device, which results in drive current degradation. This, in turn, offsets the improved mobility-driven drive current gain. A novel hard-mask-based process was developed to retain the trigate fin height after hydrogen anneal. This process demonstrated improved device characteristics for trigate FET devices, particularly for the short-channel devices.     

Modification and characterization of photo-cured sodium alginate film with ethylene glycol: effect of additives

Thin films of sodium alginate (SA) were prepared by casting from methanol solutions. Tensile strength and elongation at break (Eb%) of the films were found to be 20.4 MPa and 11.6 %, respectively. A series of SA solutions (formulations) were prepared by blending varying percentages (2–8 % by wt) of ethylene glycol (EG) and then films were prepared and cured under UV radiation at different intensities (5–35 UV passes). Monomer concentration, soaking time, and radiation dose were optimized in terms of polymer loading and mechanical properties of the cured films. For the improvement of the properties, several acrylic monomers of different functionalities as additives (2 %) like 2-ethylhexyl acrylate, 1,4-butanediol diacrylate, and trimethylolpropane triacrylate were incorporated with EG with the aid of UV radiation. Further analyses of the prepared films were characterized by FTIR and thermogravimetric analysis. Water uptake behavior was determined for the raw and cured SA films.     

Effect of Anhydride Modification on the Thermal Stability of Cultivated Acacia mangium

Abstract

This paper tests the hypothesis that propionic and succinic anhydride modification will improve the thermal stability of cultivated Acacia mangium wood. The thermal stability of modified wood was characterized with thermogravimetric analysis. Evidence of modification was confirmed by Fourier transform infrared analysis. Our results show that chemical modification with anhydrides improves the thermal stability of the Acacia wood. The higher thermal stability of anhydride-modified Acacia wood compared with unmodified wood is attributed to the reduction in hydrophilic nature of the wood due to esterification. Succinylated wood has better thermal stability than propionylated wood based on the values of on-set degradation temperatures, the temperatures at which 30, 50, and 70% degradation occurred, and the activation energy. The improved thermal stability of modified wood compared with the unmodified wood will offer potential for better utilization of Acacia mangium.     

TEMPERATURE AND THERMAL STRESSES IN A BRAKE DRUM SUBJECTED TO CYCLIC HEATING

For the optimized design of a brake drum, it appears to be very important to examine the transient temperature and thermal stress distributions in the brake drum. In the direct measurement, of them, however, a number of difficulties are involved In this study, in order to examine the initiation mechanism of the thermal crack in the brake drum, the temperature and thermal stress distributions in the brake drum in the course of their heating and cooling were investigated by using a two-dimensional axisymmetric Finite Element Method. The effect of a circumferential fin near the open end of the brake drum was also examined.     

Meshless and wavelets based complex quadrature of highly oscillatory integrals and the integrals with stationary points

In this paper, we formulate and employ efficient and accurate methods for numerical evaluation of highly oscillatory integrals and integrals having stationary points. Two new approaches using radial basis function (RBF) and wavelets are discussed. The first approach is related to meshless method (MM) which is based on multiquadric (MQ) RBF, and is specially designed for integrands having oscillatory character. This approach stems from the Levin's method. In this procedure, the solution is obtained by solving the corresponding ODE or PDE instead of finding a numerical solution of the integration problem. In situations when the integrand has stationary points, MM fails to deliver. We opt for quadrature rules based on Haar wavelets and hybrid functions. The proposed methods are tested on a number of benchmark tests considered in available literature. The performance of the new methods is compared with the existing methods. Better accuracy of the proposed methods is reported for a variety of problems.