Activation of 5-HT2 receptors facilitates depolarization of neocortical neurons by N-methyl-D-aspartate

We prospectively studied 63 children with transient hyperglycemia to determine their risk of acquiring insulin-dependent diabetes mellitus (IDDM) and to evaluate the predictive value of immunologic markers of prediabetes and of the intravenous glucose tolerance test. Children with transient hyperglycemia were identified by a prospective systematic review of the laboratory reports of a large children's hospital and an office-based pediatric practice and by referral from pediatricians. Transient hyperglycemia occurred in 0.46% of children seen in the children's hospital and in 0.013% of children attending a pediatric office practice. Insulin-dependent diabetes mellitus developed within 18 months of identification in 32% of children in whom transient hyperglycemia was discovered in the absence of a serious illness, compared with 2.3% of children identified during a serious illness (relative risk, 13.9; 95% confidence interval, 1.56 to 123.5). Islet cell antibodies and competitive insulin autoantibodies each had a 100% positive predictive value for IDDM; the negative predictive value of islet cell antibodies and competitive insulin autoantibodies was 96% and 98%, respectively. The stimulated insulin release during an intravenous glucose tolerance test, adjusted for age, had the highest overall accuracy of prediction. All children less than 6 years of age with stimulated insulin release levels < 85 pmol/L (12 microU/ml) subsequently had IDDM, as did an 11-year-old child whose stimulated insulin release level was below the 1st percentile of 170 pmol/L (24 microU/ml). To date, no child whose stimulated insulin release level was above the 5th percentile has had IDDM. We conclude that when transient hyperglycemia occurs during a serious intercurrent illness, the risk of progression to IDDM is low. In contrast, one third of children in whom transient hyperglycemia is identified without a serious illness can be expected to have IDDM within 1 year. A combination of islet cell antibodies, competitive insulin autoantibodies, and stimulated insulin release levels during an intravenous glucose tolerance test can accurately distinguish children with prediabetes from those with presumed benign transient increases in plasma glucose concentrations.     

Mine operating accurate stability control with optical fibersensing and Bragg grating technology: the European BRITE/EURAM STABILOSproject

Recent developments of stability control in mines, essentially based on Ge-doped fiber Bragg gratings (FBG) are reported including results about the different aspects of the system: accurate characterizations of FBG, sensor network topology and multiplexing method, user interface design and sensor packaging     

Processing,microstructure, and mechanical properties of hot-pressed ZrB2 ceramics with a complex Zr/Si/O-based additive

Densification behavior, microstructure, and mechanical properties of zirconium diboride (ZrB₂) ceramics modified with a complex Zr/Si/O-based additive were studied. ZrB₂ ceramics with 5–20 vol.% additions of Zr/Si/O-based additive were densified to >95% relative density at temperatures as low as 1400°C by hot-pressing. Improved densification behavior of ZrB₂ was observed with increasing additive content. The most effective additive amount for densification was 20 vol.%, hot-pressed at 1400°C (∼98% relative density). Microstructural analysis revealed up to 7 vol.% of residual second phases in the final ceramics. Improved densification behavior was attributed to ductility of the silicide phase, liquid phase formation at the hot-pressing temperatures, silicon wetting of ZrB₂ particles, and reactions of surface oxides. Room temperature strength ranged from 390 to 750 MPa and elastic modulus ranged from 440 to 490 GPa. Vickers hardness ranged from 15 to 16 GPa, and indentation fracture toughness was between 4.0 and 4.3 MPa·m^1/2. The most effective additive amount was 7.5 vol.%, which resulted in high relative density after hot-pressing at 1600°C and the best combination of mechanical properties.     

Fusing distributional and experiential information for measuring semantic relatedness

Models of semantic relatedness have usually focused on language-based distributional information without taking into account “experiential data” concerning the embodied sensorial source of the represented concepts. In this paper, we present an integrative cognitive model of semantic relatedness. The model – semantic family resemblance – uses a variation of the co-product as a mathematical structure that guides the fusion of distributional and experiential information. Our algorithm provides superior results in a set expansion task and a significant correlation with two benchmarks of human rated word-pair similarity datasets.     

Evaluating evolution: Naturalistic inquiry and the Perseus Project

Delia Neuman is an assistant professor in the College of Library and Information Services at the University of Maryland, College Park. She has written several articles on the use of naturalistic inquiry to study electronic environments, including two published in Educational Technology Research and Development: Naturalistic Inquiry and Computer-Based Instruction: Rationale, Procedures and Potential (Spring 1989) and Learning Disabled Students' Interactions with Commercial Courseware: A Naturalistic Study (Spring 1991). She is currently involved in a study funded by the American Library Association to use naturalistic methods to investigate high school students' use of CD-ROM and online databases.     

Guest Editor's Foreword: Engineering of Recon Figurable Systems

The Journal of Supercomputing -     

Calibration and evaluation of nitric acid and ammonia permeation tubes by UV optical absorption

An ultraviolet (UV) optical absorption system has been developed for absolute calibrations of nitric acid (HNO3) and ammonia (NH3) permeation tube emission rates. Using this technique, dilute mixtures containing NH3 or HNO3, both of which interact strongly with many surfaces, are accurately measured at levels below a part per million by volume. This compact and portable instrument operates continuously and autonomously to rapidly (<1 h) quantify the emission of trace gases from permeation devices that are commonly used to calibrate air-monitoring instruments. The output from several HNO3 and NH3 permeation tubes, with emission rates that ranged between 13 and 150 ng/min, was examined as a function of temperature, pressure, and carrier gas flow. Absorptions of 0.015% can be detected which allows a precision (3sigma) of +/-1 ng/min for the HNO3 and NH3 permeation tubes studied here. The accuracy of the measurements, which relies on published UV absorption cross sections, is estimated to be +/-10%. Measurements of permeation tube emission rates using ion chromatography analysis are made to further assess measurement accuracy. The output from the HNO3 and NH3 permeation tubes examined here was stable over the study period, which ranged between 3 months and 1 year for each permeation tube.     

A framework for network quality monitoring in the VoIP environment

Monitoring speech quality in Voice over IP (VoIP) networks is important to ensure a minimal acceptable level of speech quality for IP calls running through a managed network. Information such as packet loss, codec type, jitter, end‐to‐end delay and overall speech quality enables the network manager to verify and accurately tune parameters in order to adjust network problems. The present article proposes the deployment of a monitoring architecture that collects, stores and displays speech quality information about concluded voice calls. This architecture is based on our proposed MIB (Management Information Base) VOIPQOS, deployed for speech quality monitoring purposes. Currently, the architecture is totally implemented, but under adjustment and validation tests. In the future, the VOIPQOS MIB can be expanded to automatically analyze collected data and control VoIP clients and network parameters for tuning the overall speech quality of ongoing calls. Copyright © 2006 John Wiley & Sons, Ltd.