Predicting longitudinal patterns of functional deficits in children with traumatic brain injury.

Longitudinal patterns of functional deficits were investigated in 37 children with severe traumatic brain injury (TBI), 40 children with moderate TBI, and 44 children with orthopedic injuries. They were from 6 to 12 years of age when injured. Their neuropsychological, behavioral, adaptive, and academic functioning were assessed at 6 months, 12 months, and 3–5 years postinjury. Functional deficits (     

Reducing the performance-cue bias in work behavior ratings: Can groups help?

The authors examined whether the performance-cue bias can be reduced by relying on groups as raters. Study participants (N = 333) were provided with feedback regarding the performance of a workgroup and, after observing the group, assigned to an individual or group rater condition to complete a behavioral rating instrument. Results revealed that when provided with positive (vs. negative) feedback, individuals attributed more effective and fewer ineffective behaviors to the workgroup; however, group ratings were unaffected by the feedback. In addition, feedback biased the decision criteria and false alarm rates of individuals but not of groups. Discussion of when groups may attenuate versus amplify bias in performance appraisal judgments emphasizes 2 key elements--bias magnitude and task perception. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An analysis of the Candida albicans genome database for soluble secreted proteins using computer-based prediction algorithms

We sought to identify all genes in the Candida albicans genome database whose deduced proteins would likely be soluble secreted proteins (the secretome). While certain C. albicans secretory proteins have been studied in detail, more data on the entire secretome is needed. One approach to rapidly predict the functions of an entire proteome is to utilize genomic database information and prediction algorithms. Thus, we used a set of prediction algorithms to computationally define a potential C. albicans secretome. We first assembled a validation set of 47 C. albicans proteins that are known to be secreted and 47 that are known not to be secreted. The presence or absence of an N-terminal signal peptide was correctly predicted by SignalP version 2.0 in 47 of 47 known secreted proteins and in 47 of 47 known non-secreted proteins. When all 6165 C. albicans ORFs from CandidaDB were analysed with SignalP, 495 ORFs were predicted to encode proteins with N-terminal signal peptides. In the set of 495 deduced proteins with N-terminal signal peptides, 350 were predicted to have no transmembrane domains (or a single transmembrane domain at the extreme N-terminus) and 300 of these were predicted not to be GPI-anchored. TargetP was used to eliminate proteins with mitochondrial targeting signals, and the final computationally-predicted C. albicans secretome was estimated to consist of up to 283 ORFs. The C. albicans secretome database is available at http://info.med.yale.edu/intmed/infdis/candida/     

New technique for estimating thresholds of toxicity in ecological risk assessment

The use and utility of the no observed effect concentration (NOEC) in ecological risk assessment is a contentious issue. One concern is that the NOEC is not representative of a concentration at which no biologically significant effect is occurring. A new method has been developed to estimate the threshold of toxicity, or a true NOEC, for aquatic plants. The method involves determining the effective concentration (ECx) of a number of endpoints from one species. These ECx values are plotted on a log-probability scale. The x-intercept, or a low centile, of the distribution can be interpreted as the threshold of toxicity for that plant at that response level. This threshold is the concentration at which no effects should be observed for any endpoint above that response level. It is based on the assumptions that multiple effect measures from a single species will be log-normally distributed and thatthe distribution contains all possible endpoints for that species. The thresholds and the distributions can then be used as a substitute for the NOEC or ECx in risk assessment techniques, such as hazard quotients and probabilistic ecological risk assessment. This new method of estimating toxicitythresholds is more realistic than the use of arbitrary uncertainty factors, is more conservative than current probabilistic risk assessment methods, allows for simple comparison between species and exposure duration to a toxicant, and may be useful for assessing mixture toxicity. This technique was applied to field derived data with Lemna gibba, Myriophyllum spicatum, and M. sibiricumto assess potential risks from monochloroacetic acid (MCA). Using this new risk assessment method, we conclude that MCA does not appear to pose a risk to aquatic macrophytes under field conditions at current environmental concentrations.     

Patterned arrays of vertically aligned carbon nanotube microelectrodes on carbon films prepared by thermal chemical vapor deposition

A straightforward procedure is described for preparation of arrays of microdisk electrodes comprising bundles of vertically aligned carbon nanotubes (VACNTs). The arrays are fabricated by thermal chemical vapor deposition synthesis directly on a planar carbon film support. Use of standard micro- and nanolithography procedures for patterning the bilayer catalyst spots enables arrays to be grown with controlled electrode diameters and spacings. The minimum accessible VACNT bundle diameter, and hence microelectrode diameter, is 2 microm. After insulating the arrays with SU-8 epoxy and exposing the VACNT ends by polishing or treating with O2 plasma, the microdisk electrodes exhibit attractive electrochemical properties.     

The scaling of impact phenomena

A basis for scaling laws for impact phenomena is the approximation of the actual problem with a point-source problem. Point-source solutions are characterized by a single scalar coupling-parameter measure aU^μδυ of the radius a, velocity U and mass density δ of the impactor. Point-source solutions that are known to exist are discussed. The implications to scaling are developed. Recent numerical code calculations that were designed to investigate the scaling and the application of the coupling parameter are presented. Finally, a summary of some recent applications of the theory is given.     

Employment of tandem mass spectrometry for the accurate and specific identification of oligosaccharide structures

A method is described for the rapid identification of oligosaccharides employing a library of tandem MS spectra. Identification is aided by software that compares the sample tandem MS to those in the library. The method incorporates quadrupole time-of-flight mass spectrometry along with an annotated oligosaccharide (OS) structure library and the MassHunter Personal Compound Database and Library (PCDL) software. With an automated spectra search, OS structures in different samples are readily identified. This method is shown to be useful in the study of milk oligosaccharides but can be readily applied to oligosaccharide pools in other biological tissues.     

TATB thermal decomposition: An improved kinetic model for explosive safety analysis

We investigate and model the cook-off behavior of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) to understand the response of explosive systems in abnormal thermal environments. Decomposition has been explored via conventional ODTX (one-dimensional time-to-explosion), PODTX (ODTX with pressure-measurement), PyGC-MS (pyrolysis gas chromatography mass spectrometry), TGA (thermo-gravimetric analysis), DSC (differential scanning calorimetry), and IR (infrared spectroscopy) experiments under isothermal and ramped temperature profiles. The data were used to fit rate parameters for proposed reaction schemes in a MATLAB thermo-chemical computational model. These parameterizations were carried out utilizing a genetic algorithm optimization method on LLNL's high-performance computing clusters, which enabled significant parallelization. These results include a multi-step reaction decomposition model, identification of likely autocatalytic gas-phase species, accurate high-temperature sensitization, and prediction of confined system pressurization. This model will be scalable to several applications involving TATB-based explosives, like LX-17, including thermal safety models of full-scale systems.     

The ARTEMIS under‐ice AUV docking system

The ARTEMIS docking system demonstrates autonomous docking capability applicable to robotic exploration of sub‐ice oceans and sub‐glacial lakes on planetary bodies, as well as here on Earth. In these applications, melted or drilled vertical access shafts restrict vehicle geometry as well as the in‐water infrastructure that may be deployed. The ability of the vehicle to return reliably and precisely to the access point is critical for data return, battery charging, and/or vehicle recovery. This paper presents the mechanical, sensor, and software components that make up the ARTEMIS docking system, as well as results from field deployment of the system to McMurdo Sound, Antarctica in the austral spring of 2015. The mechanical design of the system allows the vehicle to approach the dock from any direction and to pitch up after docking for recovery through a vertical access shaft. It uses only a small volume of in‐water equipment and may be deployed through a narrow vertical access shaft. The software of the system reduces position estimation error with a hierarchical combination of dead reckoning, acoustic aiding, and machine vision. The system provides critical operational robustness, enabling the vehicle to return autonomously and precisely to the access shaft and latch to the dock with no operator input.