Home About us Contact
|
Home About us Contact | ||
|
|
||
Efficient Identification (efficient + identification)
Selected AbstractsIdentifying target groups for the prevention of anxiety disorders in the general populationACTA PSYCHIATRICA SCANDINAVICA, Issue 1 2010N. M. Batelaan Batelaan NM, Smit F, de Graaf R, van Balkom AJLM, Vollebergh WAM, Beekman ATF. Identifying target groups for the prevention of anxiety disorders in the general population. Objective:, To avert the public health consequences of anxiety disorders, prevention of their onset and recurrence is necessary. Recent studies have shown that prevention is effective. To maximize the health gain and minimize the effort, preventive strategies should focus on high-risk groups. Method:, Using data from a large prospective national survey, high-risk groups were selected for i) the prevention of first ever (n = 4437) and ii) either first-ever or recurrent incident anxiety disorders (n = 4886). Indices used were: exposure rate, odds ratio, population attributable fraction and number needed to be treated. Risk indicators included sociodemographic, psychological and illness-related factors. Results:, Recognition of a few patient characteristics enables efficient identification of high-risk groups: (subthreshold) panic attacks; an affective disorder; a history of depressed mood; a prior anxiety disorder; chronic somatic illnesses and low mastery. Conclusion:, Preventive efforts should be undertaken in the selected high-risk groups. [source] Output-only structural identification in time domain: Numerical and experimental studiesEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 4 2008M. J. Perry Abstract By identifying changes in stiffness parameters, structural damage can be detected and monitored. Although considerable progress has been made in this research area, many challenges remain in achieving robust structural identification based on incomplete and noisy measurement signals. The identification task is made even more difficult if measurement of input force is to be eliminated. To this end, an output-only structural identification strategy is proposed to identify unknown stiffness and damping parameters. A non-classical approach based on genetic algorithms (GAs) is adopted. The proposed strategy makes use of the recently developed GA-based method of search space reduction, which has shown to be able to accurately and reliably identify structural parameters from measured input and output signals. By modifying the numerical integration scheme, input can be computed as the parameter identification task is in progress, thereby eliminating the need to measure forces. Numerical and experimental results demonstrate the power of the strategy in accurate and efficient identification of structural parameters and damage using only incomplete acceleration measurements. Copyright © 2007 John Wiley & Sons, Ltd. [source] Quantitative assessment of human serum high-abundance protein depletionELECTROPHORESIS, Issue 21 2008Rene Stempfer Abstract The aim of this study is to quantify the effectivity of the depletion of human high-abundance serum and plasma proteins for improved protein identification and disease marker candidate discovery and to assess the risk of concomitant removal of relevant marker proteins. 2-DE and bottom-up shotgun MS combining 2-D capillary chromatography with MS/MS were applied in parallel for the analysis of fractions resulting from the depletion procedure. For many proteins the factors of enrichment by the depletion were obvious allowing their enhanced detection and identification upon high-abundance protein depletion. Nano-liquid chromatography linked MS allowed the efficient identification of several low-abundant proteins that were not identified on the 2-DE gels. Resolving the fractions that were eluted from the matrix upon depletion indicated unspecific binding of disease relevant proteins in plasma samples from acute myocardial infarction patients. The unspecific binding to the depletion matrix of inflammatory markers spiked into the serum was found to depend on the type of capturing agent used. Polyclonal avian antibodies (IgY) displayed the least unspecific binding due to the high immunogenicity of mammalian proteins in avian hosts. [source] Real-time identification of vehicle chassis dynamics using a novel reparameterization based on sensitivity invarianceINTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 2 2004S. Brennan Abstract This work presents a novel methodology to identify model parameters using the concept of sensitivity invariance. Within many classical system representations, relationships between Bode parameter sensitivities may exist that are not explicitly accounted for by the formal system model. These relationships, called sensitivity invariances, will explicitly limit the possible parameter variation of the system model to a small subspace of the possible parameter gradients. By constraining the parameter identification or adaptation to a model structure with uncoupled parameter sensitivities, a more efficient identification can be obtained at a reduced computational and modelling cost. As illustration, an identification method of using sensitivity invariance is demonstrated on an experimental problem to identify, in real time, a time-varying tire parameter associated with the chassis dynamics of passenger vehicles at highway speeds. The results are validated with simulations as well as an experimental implementation on a research vehicle driven under changing road conditions. Copyright © 2004 John Wiley & Sons, Ltd. [source] Incremental identification of fluid multi-phase reaction systemsAICHE JOURNAL, Issue 4 2009Claas Michalik Abstract Despite their importance, rigorous process models are rarely available for reaction and especially multi-phase reaction systems. The high complexity of these systems, which is due to the superposed effects of mass transfer and intrinsic reaction, is the major barrier for the development of process models. A methodology that allows thesystematic decomposition of mass transfer and chemical reaction and thus enables the efficient identification of multi-phase reaction systems is proposed in this work. The method is based on the so-called Incremental Identification Method, recently presented by Brendel et al., Chem Eng Sci. 2006;61:5404-5420. The method allows to easily test the identifiability of a system based on the available measurement data. If identifiability is given, the intrinsic reaction kinetics can be identified in a sound and numerically robust manner. These benefits are illustrated using a simulated 2-phase enzyme reaction system. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] Selection of bead-displayed, PNA-encoded chemicalsJOURNAL OF MOLECULAR RECOGNITION, Issue 5 2010Natalie R. Gassman Abstract The lack of efficient identification and isolation methods for specific molecular binders has fundamentally limited drug discovery. Here, we have developed a method to select peptide nucleic acid (PNA) encoded molecules with specific functional properties from combinatorially generated libraries. This method consists of three essential stages: (1) creation of a Lab-on-BeadÔ library, a one-bead, one-sequence library that, in turn, displays a library of candidate molecules, (2) fluorescence microscopy-aided identification of single target-bound beads and the extraction , wet or dry , of these beads and their attached candidate molecules by a micropipette manipulator, and (3) identification of the target-binding candidate molecules via amplification and sequencing. This novel integration of techniques harnesses the sensitivity of DNA detection methods and the multiplexed and miniaturized nature of molecule screening to efficiently select and identify target-binding molecules from large nucleic acid encoded chemical libraries. Beyond its potential to accelerate assays currently used for the discovery of new drug candidates, its simple bead-based design allows for easy screening over a variety of prepared surfaces that can extend this technique's application to the discovery of diagnostic reagents and disease markers. Copyright © 2009 John Wiley & Sons, Ltd. [source] An Integrated Model-Based Analysis of Polymer Chemistry and Polymerisation ReactorsMACROMOLECULAR SYMPOSIA, Issue 1 2006Charles D. Immanuel Abstract In this paper, a simple demonstration is presented on the analysis of the combined effect of polymer chemistry and the polymerisation reactor on the polymer properties. The model would ideally account for the raw material and end-product characteristics and properties on the one hand; the polymerisation kinetics and reaction engineering on the other hand. This system-wide model-driven approach enables the interlinking of the widely disparate facets of polymer science and engineering, and thereby provides a tool for rapid and efficient identification and scale-up of new polymeric materials that would be exploited in future studies. The ideas are demonstrated with regard to a hyper-branched polymerisation chemistry. [source] Quantitative analysis of phosphopeptides in search of the disease biomarker from the hepatocellular carcinoma specimenPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 12 2009Hyoung-Joo Lee Abstract Reversible phosphorylation of proteins is the most common PTM in cell-signaling pathways. Despite this, high-throughput methods for the systematic detection, identification, and quantification of phosphorylated peptides have yet to be developed. In this paper, we describe the establishment of an efficient online titaniuim dioxide (TiO2)-based 3-D LC (strong cationic exchange/TiO2/C18)-MS3 -linear ion trap system, which provides fully automatic and highly efficient identification of phosphorylation sites in complex peptide mixtures. Using this system, low-abundance phosphopeptides were isolated from cell lines, plasma, and tissue of healthy and hepatocellular carcinoma (HCC) patients. Furthermore, the phosphorylation sites were identified and the differences in phosphorylation levels between healthy and HCC patient specimens were quantified by labeling the phosphopeptides with isotopic analogs of amino acids (stable isotope labeling with amino acids in cell culture for HepG2 cells) or water (HO for tissues and plasma). Two examples of potential HCC phospho-biomarkers including plectin-1(phopho-Ser-4253) and alpha-HS-glycoprotein (phospho-Ser 138 and 312) were identified by this analysis. Our results suggest that this comprehensive TiO2 -based online-3-D LC-MS3 -linear ion trap system with high-throughput potential will be useful for the global profiling and quantification of the phosphoproteome and the identification of disease biomarkers. [source] ADLOC: An Aptamer-Displacement Assay Based on Luminescent Oxygen ChannelingCHEMISTRY - A EUROPEAN JOURNAL, Issue 36 2010Dipl.-Chem. Abstract Functional nucleic acids, such as aptamers and allosteric ribozymes, can sense their ligands specifically, thereby undergoing structural alterations that can be converted into a detectable signal. The direct coupling of molecular recognition to signal generation enables the production of versatile reporters that can be applied as molecular probes for various purposes, including high-throughput screening. Here we describe an unprecedented type of a nucleic acid-based sensor system and show that it is amenable to high-throughput screening (HTS) applications. The approach detects the displacement of an aptamer from its bound protein partner by means of luminescent oxygen channeling. In a proof-of-principle study we demonstrate that the format is feasible for efficient identification of small drug-like molecules that bind to a protein target, in this case to the Sec7 domain of cytohesin. We extended the approach to a new cytohesin-specific single chain DNA aptamer, C10.41, which exhibits a similar binding behavior to cytohesins but has the advantage of being more stable and easier to synthesize and to modify than the RNA-aptamer M69. The results obtained with both aptamers indicate the general suitability of the aptamer-displacement assay based on luminescent oxygen channelling (ADLOC) for HTS. We also analyzed the potential for false positive hits and identified from a library of 18,000 drug-like small molecules two compounds as strong singlet-oxygen quenchers. With full automation and the use of commercially available plate readers, we estimate that the ADLOC-based assay described here could be used to screen at least 100,000 compounds per day. [source] Dynamic Combinatorial Carbohydrate Libraries: Probing the Binding Site of the Concanavalin A LectinCHEMISTRY - A EUROPEAN JOURNAL, Issue 7 2004Olof Ramström Dr. Abstract Dynamic combinatorial chemistry (DCC) has emerged as an efficient approach to receptor/ligand identification based on the generation of combinatorial libraries by reversible interconversion of the library constituents. In this study, the implementation of such libraries on carbohydrate,lectin interactions was examined with the plant lectin Concanavalin A as a target species. Dynamic carbohydrate libraries were generated from a pool of carbohydrate aldehydes and hydrazide linker/scaffold components through reversible acylhydrazone exchange, resulting in libraries containing up to 474 constituents. Dynamic deconvolution allowed the efficient identification of the structural features required for binding to Concanavalin A and the selection of a strong binder, a tritopic mannoside, showing an IC50 -value of 22,,M. [source] | |||||||||||||