A comparison of SNAP II and bispectral index monitoring in patients undergoing sedation.

Clinical signs and patients' verbal responses have traditionally been used to assess patients' comfort and the depth of sedation. Recently, level-of-consciousness monitors have been used to guide sedation. The SNAP II(c) is a single-lead electroencephalogram device that displays a SNAP(c) Index - a derived value based on both high and low frequency electroencephalogram signals. Much of the current clinical research on monitoring during sedation involves the bispectral index monitor. We compared simultaneous readings recorded by the SNAP II and bispectral index during sedation in 51 consecutive patients undergoing surgery. The anaesthesia team was blinded to the SNAP II and bispectal index values. Concurrent SNAP II and bispectral index readings displayed similarly-shaped trajectories during sedation, but further studies are needed to establish the routine clinical utility of both these monitors.

Containerless measurements of thermophysical properties of Zr54Ti8Cu20Al10Ni8.

High-temperature measurement and study of reactive materials can be difficult with conventional processing methods because contamination from the measuring apparatus and container walls can adversely affect measurements. Containerless processing techniques can be employed to isolate samples from their environment, reducing contamination. Benefits of containerless processing include reduction in heterogeneous nucleation sites, which in turn delays the onset of solidification and allows the study of meta-stable undercooled phases. However, property measurements must use noncontact methods as well. Fortunately, several optical-based methods have been developed and successfully employed to measure thermophysical properties, including surface tension, viscosity, density, and thermal expansion. Combining these techniques with the electrostatic levitator (ESL) located at the NASA Marshall Space Flight Center (MSFC) has resulted in an excellent facility to perform containerless material studies which support microgravity flight projects. Currently, studies of the thermophysical properties of liquid quasi-crystal forming and related alloys ranging from superheated to deeply undercooled states are being done with this facility in support of the NASA-funded flight project Quasi-crystalline Undercooled Alloys for Space Investigation (QUASI). While the primary purpose of these measurements is to support planned flight experiments, they are also a desirable resource for future manufacturing considerations and for fundamental insight in the physics of icosahedral ordering in liquids and solids. Presented here is an overview of the contactless measuring methods for surface tension, viscosity, density, and thermal expansion applied to Zr54Ti8Cu20Al10Ni8, for the superheated and meta-stable undercooled liquid phases, in support of QUASI.

Medicare Transaction System: platform for change.

This article provides an overview of the Medicare Transaction System (MTS), a Health Care Financing Administration (HCFA)-wide initiative to be implemented starting in 1997 which will develop a national, standard, integrated, government-owned, contractor-operated Medicare claims processing system that will meet the challenges confronting Medicare over the next 2 decades. The authors discuss MTS goals and objectives, major features, how it will work, standardization efforts being undertaken in support of the initiative, contracting efforts involved, and project status.

Detection of mutagens in the urine of rats following topical application of hair dyes.

Mutagens were detected in the urine of rats following topical application of two commercial oxidative-type hair dye preparations. The test system used was induction of back mutation with the bacterial tester strain TA1538, a histidine-dependent mutant of Salmonella typhimurium. Various quantities of dye were applied to the shortened hair on the backs of the test animals. The dye was allowed to remain on the hair for 20 min after application and was then removed by shampooing and thorough rinsing. Maximal levels of mutagenic activity occurred with urine collected during first 24 h following dye application, and a dose--response was observed when increasing volumes of mutagenic urine were tested. Mutagens were detected in rat urine after intraperitoneal injection, and also after topical application of 4-nitro-o-phenylenediamine, one of the constituents of the hair-dye preparations.

Case report: thrombosis of the inferior vena cava--an unusual presentation of protein C deficiency.

In children, venous thrombosis is uncommon and this is true particularly for one of the inferior vena cava. Recurrent superficial venous thrombosis is a well-recognized presenting symptom of Protein C deficiency but thrombosis of the inferior vena cava as the initial manifestation of this condition has only rarely been reported. We present a case of a 13-year-old boy in whom the first indication of Protein C deficiency was an isolated thrombosis in the intra-hepatic inferior vena cava noted on a routine ultrasound examination.

Motor variables correlated with the hand-to-mouth maneuver in stroke patients.

This study investigated the relationship between each of three independent variables and the completion of the hand-to-mouth maneuver in 23 hemiparetic stroke patients. The independent variables were elbow-extensor muscle tone (graded using the Modified Ashworth Scale); active elbow-flexion range-of-motion deficit measured without the influence of gravity; and elbow-flexion strength measured without the influence of gravity with a hand-held dynamometer. The hand-to-mouth maneuver was graded according to the degree of completion using a three-level ordinal scale. Spearman (rs) correlations demonstrated a significant relationship between the extent of completion of the hand-to-mouth maneuver and both the active elbow-flexion-range deficit (rs = -.853) and the elbow-flexor muscle force (rs = .829). The correlation of the maneuver with elbow-extensor muscle tone (rs = -.063) was not significant, but the relationship may have been influenced by the fact that only a minority of subjects had elevated tone, and that elevation was minimal. The result suggest that both active-movement deficits and muscle strength may be important to upper extremity function.

On-probe solid-phase extraction/MALDI-MS using ion-pairing interactions for the cleanup of peptides and proteins.

Samples originating from biological sources often contain a complex mixture of inorganic salts, buffers, chaotropic agents, surfactants/detergents, preservatives, and other solubilizing agents. However, the presence of these contaminants virtually ensures the failure of any subsequent analysis of the sample by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). Sample cleanup procedures, therefore, must be performed prior to MALDI-MS analysis. This paper reports a probe-surface derivatization method that greatly simplifies this sample preparation process. MALDI probes possessing self-assembled monolayers (SAMs) terminated with ionic functional groups can rapidly extract peptides/proteins via ionic interactions from < or = 1-microL volumes of sample solutions placed directly on their surface. We have found that MALDI probes modified in this manner are a practical solution for analyzing very small volumes of peptide/protein solutions contaminated with high levels of inorganic salts, buffers, detergents, chaotropic agents, and other solubilizing agents.

Polarization-sensitive subwavelength antireflection surfaces on a semiconductor for 975 nm.

We present the results of subwavelength antireflection surfaces etched into GaAs for use at 975 nm. These surfaces comprise linear gratings with periods less than the wavelength of light in GaAs. The structure appears as a homogeneous birefringent film. For one of the two polarizations, the film is directly analogous to the well-known quarter-wavelength antireflection coating. For the other polarization there is little effect on the surface reflectivity.

High-efficiency subwavelength diffractive optical element in GaAs for 975 nm.

We have fabricated subwavelength diffractive optical elements with binary phase profiles for operation at 975 nm. The individual surface-relief features of the elements are smaller than the wavelength of light in the material. By modulating the size and spacing of the features we form artificial, gradient, effective index-of-refraction surfaces. The blazed transmission gratings were designed with rigorous coupled-wave analysis and fabricated by direct-write electron-beam lithography and reactive ion-beam etching in GaAs. The gratings have minimum features 63 nm wide. Transmission measurements show 85% diffraction efficiency into the first order.

Tandem mass spectrometric analysis of aspergillus niger pectin methylesterase: mode of action on fully methyl-esterified oligogalacturonates.

The substrate specificity and the mode of action of Aspergillus niger pectin methylesterase (PME) was determined using both fully methyl-esterified oligogalacturonates with degrees of polymerization (DP) 2-6 and chemically synthesized monomethyl trigalacturonates. The enzymic activity on the different substrates and a preliminary characterization of the reaction products were performed by using high-performance anion-exchange chromatography at neutral pH. Electrospray ionization tandem MS (ESI-MS/MS) was used to localize the methyl esters on the (18)O-labelled reaction products during the course of the enzymic reaction. A. niger PME is able to hydrolyse the methyl esters of fully methyl-esterified oligogalacturonates with DP 2, and preferentially hydrolyses the methyl esters located on the internal galacturonate residues, followed by hydrolysis of the methyl esters towards the reducing end. This PME is unable to hydrolyse the methyl ester of the galacturonate moiety at the non-reducing end.

Microtags with 150-nm line gratings fabricated by use of extreme-ultraviolet lithography.

The microtag concept is an anticounterfeiting and security measure. Microtags are computer-generated holograms (CGH's) consisting of 150-nm lines arranged to form 300-nm-period gratings. The microtags that we describe were designed for readout at 442nm . The smallest microtag measures 56micromx80 microm when viewed at normal incidence. The CGH design process uses a modified iterative Fourier-transform algorithm to create either phase-only or phase-and-amplitude microtags. We also report on a simple and compact readout system for recording the diffraction pattern formed by a microtag. The measured diffraction patterns agree very well with predictions.

Mass-producible microscopic computer-generated holograms: microtags.

We have developed a method for encoding phase and amplitude in microscopic computer-generated holograms (microtags) for security applications. An 8 x 8 cell phase-only and an 8 x 8 cell phase-and-amplitude microtag design has been exposed in photoresist by the extreme-ultraviolet (13.4-nm) lithography tool developed at Sandia National Laboratories. Each microtag measures 80 microm x 160 microm and contains features that are 0.2 microm wide. Fraunhofer zone diffraction patterns can be obtained from fabricated microtags without any intervening optics and compare favorably with predicted diffraction patterns.