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In times of crisis and confusion, we often turn to stories for comfort, courage, and a measure of guidance. For the bewildered traveler, stories may serve as a much-needed map [...]

This paper analyses the nickel based superalloy Inconel 713C casts typically used in high and low pressure turbines of aircraft engines. The ingots were manufactured in the Research and Development Laboratory for Aerospace Materials at the Rzeszów University of Technology. The superalloy structures were analysed by the following methods: X-ray diffraction orientation measurement and ultrasonic wave propagation. Ultrasonic techniques are mainly used to measure the blade wall’s thickness. Measurement accuracy is determined by the velocity of the ultrasonic wave in the material tested. This work evaluates the effect of the nickel-based superalloy microstructure on the velocity of the ultrasonic wave propagation. Three different macrostructures: equiax (EQ), directionally solidified (DS) and single crystal (SX) were analysed. The authors determined the crystal misorientation in the obtained casts as the deviation of [001] crystallographic direction from the withdrawal axis or the main axis of the ingots. The measurements performed allowed researchers to identify significant differences in the wave velocity between EQ, DS and SX structures.

Describes an arts and drama program in New Jersey which celebrates and explores cultural diversity. Outlines the seven-week workshop series (beginning with a dramatization of the Tower of Babel myth) that introduces art, music, and traditional stories of various cultures. Concludes with a festival where children dramatize stories they have learned. (PRA)

A new generation of microscale, nuclear magnetic resonance (CapNMR) probe technology employs two independent detection elements to accommodate two samples simultaneously. Each detection element in the dual-sample CapNMR probe (DSP) delivers the same spectral resolution and S/N as in a CapNMR probe configured to accommodate one sample at a time. A high degree of electrical isolation allows the DSP to be used in a variety of data acquisition modes. Both samples are shimmed simultaneously to achieve high spectral resolution for simultaneous data acquisition, or alternatively, a flowcell-specific shim set is readily called via spectrometer subroutines to enable acquisition from one sample while the other is being loaded. An automation system accommodates loading of two samples via dual injection ports on an autosampler and two completely independent towpaths leading to dedicated flowcells in the DSP probe. 10.1021/ac101003f

A microflow CapNMR probe double-tuned for [sup.1]H and [sup.13]C was installed on a 400-MHz NMR spectrometer and interfaced to an automated liquid handler. Individual samples dissolved in DMSO-[d.sub.6] are submitted for NMR analysis in vials containing as little as 10 [micro]L of sample. Sets of samples are submitted in a low-volume 384-well plate. Of the 10 [micro]L of sample per well, as with vials, 5 [micro]L is injected into the microflow NMR probe for analysis. For quality control of chemical libraries, 1D NMR spectra are acquired under full automation from 384-well plates on as many as 130 compounds within 24 h using 128 scans per spectrum and a sample-to-sample cycle time of ~11 min. Because of the low volume requirements and high mass sensitivity of the microflow NMR system, 30 nmol of a typical small molecule is sufficient to obtain high-quality, well-resolved, 1D proton or 2D COSY NMR spectra in ~6 or 20 min of data acquisition time per experiment, respectively. Implementation of pulse programs with automated solvent peak identification and suppression allow for reliable data collection, even for samples submitted in fully protonated DMSO. The automated microflow NMR system is controlled and monitored using web-based software.

The mobile robot surrogate (MRS) method, as a means for developing autonomy in complex systems, is presented. Used to analyze and interpret sonar data for landmark identification and navigation, this method involves: 1) putting a human operator within a telerobotic loop; 2) studying the capabilities and limitations of the operator for different tasks; 3) using protocol analysis to extract the knowledge from the operator into an expert system; 4) substituting the expert system for the operator within the robotic loop. A central aspect of the MRS methodology is that the operator, through the telerobotic interface, is limited to the same sensor information as the robot. The strength of this methodology is shown through the development of door identification and door traversal performances by an autonomous mobile robot using ultrasonic data. Index Terms - Autonomy, door identification, door traversal, mobile robot surrogate, mobile robots, navigation, protocol analysis, ultrasonic sonars.

Intestinal function is impaired in malnutrition. Because oxidative stress is a component of gastrointestinal injury, and malnutrition may reduce antioxidant defenses, we investigated the involvement of oxidative stress in the intestinal dysfunction due to malnutrition. Weanling rats were fed either a normal protein (22% casein) or a low protein (6% casein) diet for 4 wk. In intestinal homogenates, we assessed free radical damage and enzymatic antioxidant defenses. In jejunal fragments mounted in Ussing chambers, we measured ionic transport by short-circuit current (Isc) and protein permeability by transepithelial fluxes of Beta-lactoglobulin. Catalase activity and the thiobarbituric acid-reacting substances concentration were greater in intestinal mucosa of the low protein group, whereas the glutathione concentration and the activities of superoxide dismutase and Se-dependent glutathione peroxidase were the same as in the normal protein group intestinal mucosa. Both basal Isc and the Delta-Isc induced by glucose and forskolin, as well as Beta-lactoglobulin fluxes, were higher in the low protein group. Exogenous H2O2 stress increased Isc significantly more in the low protein than the normal protein group but did not alter protein permeability. These results show that malnutrition induces both intestinal free radical damage and altered epithelial transport, suggesting that oxidative stress may contribute to the intestinal dysfunction associated with malnutrition.