WISC-III and CAS: Which Correlates Higher with Achievement for a Clinical Sample?

The relationships between Wechsler Intelligence Scale for Children-Third Edition (WISC-III) and the Cognitive Assessment System (CAS) with the Woodcock-Johnson Tests of Achievement (WJ-III) were examined for a sample of 119 children (87 males and 32 females) ages 6 to 16. The sample was comprised of children who were referred to a specialty clinic for evaluation. Participants were administered the WISC-III, the CAS, and the WJ-III, in that order. Results indicated that CAS/WJ-III correlations were consistently significantly higher than those found for the WISC-III/WJ-III. The four separate CAS scales added more variance above and beyond the four separate WISC-III scales than the WISC-III added above and beyond the CAS. In addition, the CAS Full Scale accounted for more unique variance and was a stronger predictor of WJ-III Academic Skills Cluster than the WISC-III Full Scale IQ. These results support the validity of the Planning, Attention, Simultaneous, and Successive theory as measured by the CAS in relation to the general intelligence model measured using the WISC-III for explaining variance in achievement for this clinical sample. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Graded balloon dilation atrial septostomy in severe primary pulmonary hypertension. A therapeutic alternative for patients nonresponsive to vasodilator treatment

Endothelial cell cultures were established from several wild African mammalian species. Long-term cultures were established from three ruminants, stable antelope (Hippotragus niger), buffalo (Syncerus caffer), and eland (Tragelaphus oryx), and from an omnivore, the bushpig (Potamochoerus porcus). Cowdria ruminanntium was isolated from plasma of clinically affected animals in these four cell lines and in bovine endothelial cells used routinely for C. ruminantium propagation. Nineteen different strains of C. ruminantium from Africa and the Caribbean region were grown and maintained in these cell lines and their growth was comparable with growth in the bovine endothelial cells. The role of sable antelope, eland, and bushpigs in the epidemiology of heartwater is unknown. However, these results extend the number of cell lines that can be used to isolate and grow C. ruminantium.     

Tuning an adaptive controller using a robust control approach

This article proposes a new technique for the tuning of a discrete adaptive controller that is designed based on Lyapunov stability concepts. The tuning is based on the minimisation of a performance index that can be calculated from a generalised eigenvalue problem (GEVP) using LMI's (Linear Matrix Inequalities). The proposed technique results in an adaptive controller with time-varying tuning gains. The solution is based on an approximation of the optimal dual adaptive control problem. The tuning technique was used to perform on-line control of a first-order system and an isothermal and a non-isothermal CSTR. The results show that the proposed approach provides better performance than an adaptive algorithm with the same structure, but with constant adaptation gains. Also, the proposed algorithm is shown to be superior to an adaptive controller based on a Recursive Least Squares (RLS) estimator during sudden changes in model parameters.     

Current challenges in the design and control of multiscale systems

Multiscale modelling is a new emerging field in process systems engineering. Although the idea of linking events occurring across time and length scales is not new, the numerical solution of these models is challenging because of computational limitations and the difficulty in coupling modelling methods with different characteristics. Although an extensive set of tools are currently available to improve the performance of processes described using continuum models, most of these tools are not suitable to design and control a multiscale process. This work presents the approaches that are currently available to perform multiscale modelling and identifies the key challenges that need to be addressed to improve the performance of macroscopic processes by controlling events occurring at the atomistic, molecular and nanoscopic levels.     

Treatment of petroleum production wastewater for reuse in secondary oil recovery.

Petroleum production wastewater is highly saline and contains large amounts of Ca, Mg, sulphides and hydrocarbons. The reuse of this wastewater in the secondary oil recovery can provide pollution prevention and water conservation benefits. Injection of water to the oil deposits is a frequently used method for secondary oil recovery. This operation is performed at high pressures and temperatures, because of which a suitable water quality is required to avoid deposit formation, scaling and clogging effects. The objective of this study was to select the best treatment system for the oil production wastewater, generated in one of the Mexican oil extraction facilities, for the implementation of this kind of reuse by injecting the treated water to sand formations with 12-15% porosity. A complete characterization of the petroleum production wastewater was done. Based on laboratory tests, three basic treatment options were suggested and evaluated in a pilot plant. The most suitable treatment was determined by injecting the different treated waters in samples of the real formations. The selected system consists in softening, followed by oxidation, decarbonation and filtration. This train allowed 99.8% hardness removal, a complete S(2-) removal, as well as 99% TSS, 78% TOC, 98% Sr, 86% Ba, 51% Si and 17% Fe removals.     

Bandwidth renegotiation scheme for VBR video services

The authors show how the existence of long term variability in variable bit rate (VBR) video traffic imposes the need for bandwidth renegotiation. In particular, two simple scenarios with a fixed renegotiation interval are considered. Using a real MPEG trace, the renegotiation scheme is evaluated to prove its benefits in terms of bandwidth gain and quality of service. The problem of renegotiation demonstrates the need for modelling long term variability in VBR traffic     

Multifoveal imager for stereo applications

A multiresolution imager based on adaptive retinal structures, with data compressions above 85%, is presented in this article. The main goal of the imager platform is to speed up image processing with the use of selective data reductions to shorten the vision systems' tasks in stereo applications. Implemented on a field‐programmable gate array, the platform can be configured as the front end of active vision systems, with use of adaptive foveal sensing on uniresolution images to cover wide fields of view, being also a development tool for multiresolution applications with different image formats and interfaces. The multifoveal imager provides the hierarchical data structures related to multiresolution levels, following instructions to control sensor parameters or to perform adaptive fovea fixations in real time, adapting its operation to the constraints of the active vision systems. It also uses intermediate resolution data to implement in hardware an efficient background extractor to cooperate with image processors in motion detection tasks and attention mechanisms. Some platform configurations are explained and experimental results are discussed in relation to the advantages of the adaptive retinal structures. © 2002 Wiley Periodicals, Inc. Int J Imaging Syst Technol 12, 149–165, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.10023