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Developed Methods (developed + methods)
Selected AbstractsComputer-assisted 2-D agarose electrophoresis of Haemophilus influenzae type B meningitis vaccines and analysis of polydisperse particle populations in the size range of viruses: A reviewELECTROPHORESIS, Issue 4 2007Dietmar Tietz Dr. Abstract When protein,polysaccharide conjugated vaccines were first developed for the immunization of small children against meningitis caused by infection with Haemophilus influenzae type b (Hib), the vaccine preparations varied in immunogenicity. Testing for immunogenicity was time-consuming and alternative analytical procedures for determining vaccine quality were unsatisfactory. For example, due to the very high molecular weight of the vaccine particles, immunogens could only be physically characterized as a fraction in the void volume of Sepharose gel filtration. In search of better analytical methods, a computer-assisted electrophoretic technique for analyzing such vaccines was developed in the period from 1983 to 1995. This new approach made it possible to analyze highly negatively charged particles as large as or larger than intact viruses. 2-D gel patterns were generated that varied depending on the conditions of the particular vaccine preparation and were therefore characteristic of each vaccine sample. Thus, vaccine particle populations with a continuous size variation over a wide range (polydisperse) could be characterized according to size and free mobility (related to particle surface net charge density). These advances are reviewed in this article, since the developed methods are still a promising tool for vaccine quality control and for predicting immunogen effectiveness in the production of vaccines. The technique is potentially beneficial for Hib immunogens and other high-molecular-mass vaccines. Additional biomedical applications for this nondenaturing electrophoretic technique are briefly discussed and detailed information about computational and mathematical procedures and theoretical aspects is provided in the Appendices. [source] Interactive force control of an operator,mobile manipulator coordination systemJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 4 2002Jae H. Chung In this article, a new type of coordination control called interactive force control is developed for an operator,mobile manipulator coordination system (OMMCS) based on a base force/torque sensor. In the interactive force control scheme, a robust force control of the manipulator and impedance control of the mobile platform are integrated to achieve smooth interaction between the operator, the manipulator, and the mobile platform. In simulation, the developed methods are compared for control performance in tracking and force regulation. Simulation results show the promise of the developed control scheme, which utilizes robust force control based on a base force/torque sensor. © 2002 Wiley Periodicals, Inc. [source] Automated judgment of document qualitiesJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 9 2006Kwong Bor Ng The authors report on a series of experiments to automate the assessment of document qualities such as depth and objectivity. The primary purpose is to develop a quality-sensitive functionality, orthogonal to relevance, to select documents for an interactive question-answering system. The study consisted of two stages. In the classifier construction stage, nine document qualities deemed important by information professionals were identified and classifiers were developed to predict their values. In the confirmative evaluation stage, the performance of the developed methods was checked using a different document collection. The quality prediction methods worked well in the second stage. The results strongly suggest that the best way to predict document qualities automatically is to construct classifiers on a person-by-person basis. [source] Measuring the spillover effects: Some Chinese evidence,PAPERS IN REGIONAL SCIENCE, Issue 1 2000Long Gen Ying Chinese space economy; core-periphery analysis; local Moran; spillover effects Abstract. Based on recently developed methods of exploratory spatial data analysis, this article seeks to prove the desired spread effects in the Chinese space economy from a core-periphery perspective. Recently developed methods of exploratory spatial data analysis provide new insights on the spatial pattern of the interaction of Chinese provincial output growth rates over the 1978,1994 period. Findings indicate that the economic spillover effects are most evident at the first order of province contiguity from Guangdong, where the two coastal provinces of Hainan and Guangxi are identified with a significant spread pattern, while non-coastal provinces Hunan and Jiangxi are observed with a strong polarization pattern. A further analysis indicates that the state preferential policies favoring the coastal region are the fundamental force in determining the direction of spread-polarization processes in the Chinese space economy. This finding confirms Friedmann's hypothesis on spatial interaction, namely, that the spread process is a successful diffusion of the core's existing institutions into the periphery. [source] Isotope ratio mass spectrometry coupled to liquid and gas chromatography for wine ethanol characterizationRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 20 2008Ana I. Cabañero Two new procedures for wine ethanol 13C/12C isotope ratio determination, using high-performance liquid chromatography and gas chromatography isotope ratio mass spectrometry (HPLC/IRMS and GC/IRMS), have been developed to improve isotopic methods dedicated to the study of wine authenticity. Parameters influencing separation of ethanol from wine matrix such as column, temperature, mobile phase, flow rates and injection mode were investigated. Twenty-three wine samples from various origins were analyzed for validation of the procedures. The analytical precision was better than 0.15,, and no significant isotopic fractionation was observed employing both separative techniques coupled to IRMS. No significant differences and a very strong correlation (r,=,0.99) were observed between the 13C/12C ratios obtained by the official method (elemental analyzer/isotope ratio mass spectrometry) and the proposed new methodology. The potential advantages of the developed methods over the traditional one are speed (reducing time required from hours to minutes) and simplicity. In addition, these are the first isotopic methods that allow 13C/12C determination directly from a liquid sample with no previous ethanol isolation, overcoming technical difficulties associated with sample treatment. Copyright © 2008 John Wiley & Sons, Ltd. [source] Development of a liquid chromatography/electrospray selected reaction monitoring method for the determination of organoarsenic species in marine and freshwater samplesRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 19 2006Richard Schaeffer Cation- and anion-exchange high-performance liquid chromatography/electrospray selected reaction monitoring (HPLC/ES-SRM) methods were developed for the determination of 15 organoarsenic compounds in marine and freshwater samples. The results demonstrate that the developed HPLC/ES-SRM methods are powerful approaches for the identification of organoarsenic species in crude sample extracts. The detection limits, linearity as well as reproducibility for most of the species are comparable or even better than those measured by the HPLC/inductively coupled plasma mass spectrometry (ICPMS) technique. The qualitative analysis of the extracts shows that the developed methods allow for the identification of arsenicals which were not detectable by ICPMS. It was also demonstrated that the signal suppression caused by matrix effects means a significant limitation in the quantification of arsenicals by ES-SRM detection. This drawback is manifested especially in the case of the slightly retained species. The three sample-cleanup chromatographic methods including off-line size-exclusion, on-line reversed-phase and on-line oppositely charged ion-exchange approaches proved to be ineffective for separation of the signal-suppressive matrix from the analytes. The standard addition calibration seems to be a suitable solution for such problems. Copyright © 2006 John Wiley & Sons, Ltd. [source] Some contributions to the analysis of multivariate dataBIOMETRICAL JOURNAL, Issue 2 2009Arne C. Bathke Abstract In this paper, we provide an overview of recently developed methods for the analysis of multivariate data that do not necessarily emanate from a normal universe. Multivariate data occur naturally in the life sciences and in other research fields. When drawing inference, it is generally recommended to take the multivariate nature of the data into account, and not merely analyze each variable separately. Furthermore, it is often of major interest to select an appropriate set of important variables. We present contributions in three different, but closely related, research areas: first, a general approach to the comparison of mean vectors, which allows for profile analysis and tests of dimensionality; second, non-parametric and parametric methods for the comparison of independent samples of multivariate observations; and third, methods for the situation where the experimental units are observed repeatedly, for example, over time, and the main focus is on analyzing different time profiles when the number p of repeated observations per subject is larger than the number n of subjects. [source] Analysis of Times to Repeated Events in Two-Arm Randomized Trials with Noncompliance and Dependent CensoringBIOMETRICS, Issue 4 2004Shigeyuki Matsui Summary This article develops randomization-based methods for times to repeated events in two-arm randomized trials with noncompliance and dependent censoring. Structural accelerated failure time models are assumed to capture causal effects on repeated event times and dependent censoring time, but the dependence structure among repeated event times and dependent censoring time is unspecified. Artificial censoring techniques to accommodate nonrandom noncompliance and dependent censoring are proposed. Estimation of the acceleration parameters are based on rank-based estimating functions. A simulation study is conducted to evaluate the performance of the developed methods. An illustration of the methods using data from an acute myeloid leukemia trial is provided. [source] | ||||||||||