Interactive visualization for rapid noninvasive cardiac assessment

New interactive computerized visualization technology promises to give doctors easier, quicker and less expensive ways to determine whether and to what extent patients have heart disease. This new visualization technology, combined with new image acquisition methods, may allow doctors to take the results of one noninvasive cardiac examination and produce a variety of 3D displays that can be easily manipulated to reveal problems that are not presently accessible without multiple costly assessments. The MRI technique is ahead of the capability of computerized visualization tools to analyze and display the resulting data. The visualization developments we discuss in this paper make both raw MRI data and derived information, such as heart wall contraction rate estimates, directly accessible to doctors     

Smallest space analysis of intelligence and achievement tests.

Smallest space analysis is more parsimonious than factor analysis in the sense that it usually renders a space of fewer dimensions. Interpretation of such a space is facilitated by an a priori definitional system for the variables being studied. A reanalysis of the intercorrelation matrix in a previous study by D. J. Hoger by means of the Guttman-Lingoes SSA-I computer program shows how a certain definitional structure of the test variables is reflected in a 2-space. Contiguous regions in this space represent the task of the S rule-inferring, rule-applying, and school achievement and the language of presentation of the item: verbal, digital, and figural. The 6 orthogonal common factors extracted by Hoger's factor analysis can be represented as 6 points in a 2-space simultaneously with the tests. Results add further confirmation to the utility of the faceted definition of intelligence and the radex hypothesis for the structure of test interrelationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Methodological challenges in evaluating performance, impact and ranking of IWRM strategies in the Jordan Valley

The philosophy of integrated water resource management (IWRM), as formulated in several international summits, yielded numerous interpretations and extensions over the last decade but always focused on the overall objective of maximizing the welfare and livelihood of the people concerned. One of the major constraints of this concept is the gap between the well-defined philosophy and the fuzzy definition of operational and testable indicators for the achievement of its goals. This leads to difficulties in the evaluation of potential contributions from technological and managerial improvements. The experience of the multi-lateral IWRM research initiative SMART in the lower Jordan Valley shows that the evaluation and ranking of alternative IWRM strategies and their elements relies simultaneously on the identification of local goals and their interfaces with the superordinate national water sector policies. The documentation of the, still ongoing, development process of suitable assessment procedures describes their methodological embedding and conclusions drawn for the heterogeneous situation of water-related settings in this transboundary watershed.     

Synthesis of Polymerizable Cyclodextrin Derivatives for Use in Adhesion-Promoting Monomer Formulations

The synthesis of the cyclodextrin derivatives reported herein was assisted by extensive literature research together with structure-property relationships derived from three-dimensional molecular modeling. These studies led to the hypothesis that many of the 21 hydroxyl groups on beta-cyclodextrin molecules could be derivatized to form a closely related family of analogous chemical compounds containing both polymerizable groups and hydrophilic ionizable ligand (substrate-binding) groups, each attached via hydrolytically-stable ether-linkages. The vinylbenzylether polymerizable groups should readily homopolymerize and also copolymerize with methacrylates. This could be highly useful for dental applications because substantially all contemporary dental resins and composites are based on methacrylate monomers. Due to hydrophilic ligands and residual hydroxyl groups, these cyclodextrin derivatives should penetrate hydrated layers of dentin and enamel to interact with collagen and tooth mineral. Analyses indicated that the diverse reaction products resulting from the method of synthesis reported herein should comprise a family of copolymerizable molecules that collectively contain about 30 different combinations of vinylbenzyl and hexanoate groups on the various molecules, with up to approximately seven of such groups combined on some of the molecules. Although the hypothesis was supported, and adhesive bonding to dentin is expected to be significantly improved by the use of these polymerizable cyclodextrin derivatives, other efforts are planned for improved synthetic methods to ensure that each of the reaction-product molecules will contain at least one copolymerizable moiety. The long-term objective is to enable stronger and more durable attachments of densely cross-linked polymers to hydrated hydrophilic substrates. Capabilities for bonding of hydrolytically stable polymers to dental and perhaps other hydrous biological tissues could provide widespread benefits.     

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry interlaboratory comparison of mixtures of polystyrene with different end groups: statistical analysis of mass fractions and mass moments

A matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) interlaboratory comparison was conducted on mixtures of synthetic polymers having the same repeat unit and closely matching molecular mass distributions but with different end groups. The interlaboratory comparison was designed to see how well the results from a group of experienced laboratories would agree on the mass fraction, and molecular mass distribution, of each polymer in a series of binary mixtures. Polystyrenes of a molecular mass near 9000 u were used. Both polystyrenes were initiated with the same butyl initiator; however, one was terminated with -H (termed PSH) and the other was terminated with -CH2CH2OH (termed PSOH). End group composition of the individual polymers was checked by MALDI-TOF MS and by nuclear magnetic resonance (NMR). Five mixtures were created gravimetrically with mass ratios between 95:5 and 10:90 PSOH/PSH. Mixture compositions where measured by NMR and by Fourier transform infrared spectrometry (FT-IR). NMR and FT-IR were used to benchmark the performance of these methods in comparison to MALDI-TOF MS. Samples of these mixtures were sent to any institution requesting it. A total of 14 institutions participated. Analysis of variance was used to examine the influences of the independent parameters (participating laboratory, MALDI matrix, instrument manufacturer, TOF mass separation mode) on the measured mass fractions and molecular mass distributions for each polymer in each mixture. Two parameters, participating laboratory and instrument manufacturer, were determined to have a statistically significant influence. MALDI matrix and TOF mass separation mode (linear or reflectron) were found not to have a significant influence. Improper mass calibration, inadequate instrument optimization with respect to high signal-to-noise ratio across the entire mass range, and poor data analysis methods (e.g., baseline subtraction and peak integration) seemed to be the greatest obstacles in the correct application of MALDI-TOF MS to this problem. Each of these problems can be addressed with proper laboratory technique.     

Manganese mobilization and enrichment during soil aquifer treatment (SAT) of effluents, the Dan Region Sewage Reclamation Project (Shafdan), Israel

The composition of groundwater reclaimed from tertiary soil aquifer treatment systems reflects the dynamic processes taking place in the subsurface, between the infiltration basin and the production wells. At the end of year 2000, following more than a decade of operation, high Mn concentrations (2 micromol L(-1) < or = Mn < or = 40 micromol L(-1)) appeared in the reclaimed effluents of the Dan Region Sewage Reclamation Project (Shafdan), Israel. A mass balance indicates that the high Mn excess originated from the aquifer rocks, most likely following reduction of sedimentary Mn-oxides under suboxic conditions. The subsequent adsorption of the Mn2+ results in a slow Mn2+ front that advances in the direction of groundwater flow only when all the Mn2+ exchangeable sites are saturated. A retardation factor obtained from two independent estimates based on a simple reduction-adsorption-advection model yields a value of about 10. This explains the delayed appearance of the high Mn concentrations at a distance of only -500 m from the infiltration basin.     

Rapid high-resolution characterization of functionally important monoclonal antibody N-glycans by capillary electrophoresis

Characterization of the N-glycosylation present in the Fc region of therapeutic monoclonal antibodies requires rapid, high-resolution separation methods to guarantee product safety and efficacy during all stages of process development. Determination of fucosylated oligosaccharides is particularly important during clone selection, product characterization, and lot release as fucose has been shown to adversely affect the ability of mAbs to induce antibody dependent cellular cytotoxicity (ADCC). Here, we apply a general capillary electrophoresis optimization strategy to separate functionally relevant fucosylated and afucosylated glycans on mononclonal antibody products in the presence of several high mannose oligosaccharides. The N-glycans chosen represent those most commonly reported on CHO cell derived therapeutic antibodies. A rapid (<7 min) high-resolution separation of 12 commonly reported and functionally important IgG glycans was developed by systematically evaluating the effects of selectivity (boric acid) and efficiency (linear polyacrylamide) enhancing additives. The approach can be used to rapidly optimize capillary electrophoresis separation of other glycan mixtures. Following optimization, the method was applied to overnight sample processing for automated 96 well plate-based glycosylation analyses of two nonproprietary therapeutic monoclonal antibodies, demonstrating ruggedness and suitability for high-throughput process and product monitoring applications.     

Rigorous automated network security management

Achieving a security goal in a networked system requires the cooperation of a variety of devices, each device potentially requiring a different configuration. Many information security problems may be solved with appropriate models of these devices and their interactions, giving a systematic way to handle the complexity of real situations.We present an approach, rigorous automated network security management, that front-loads formal modeling and analysis before problem solving, thereby providing easy-to-run tools with rigorously justified results. With this approach, we model the network and a class of practically important security goals. The models derived suggest algorithms that, given system configuration information, determine the security goals satisfied by the system. The modeling provides rigorous justification for the algorithms, which may then be implemented as ordinary computer programs requiring no formal methods training to operate.We have applied this approach to several problems. In this paper we describe two: distributed packet filtering and the use of IP security (IPsec) gateways. We also describe how to piece together the two separate solutions to these problems, jointly enforcing packet filtering as well as IPsec authentication and confidentiality on a single network.