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Analysis Experiments (analysis + experiment)
Selected AbstractsTeaching the Fuzzy Front End of Innovation: Experimenting with Team Learning and Cross-Organizational IntegrationCREATIVITY AND INNOVATION MANAGEMENT, Issue 3 2009Miia Martinsuo How can the extremely uncertain front end of innovation , managing the fuzzy front end , be taught to graduate students? This paper describes and analyses experiments with experiential, problem-based learning focused on the front end of innovation. The focus is on the learning and cross-organizational integration of student teams; factors that have been identified as central to the success of teams involved in the front end of innovation. An experiential course, ,From an idea to a business plan in product development', was developed in conjunction with an actual company, and piloted with four student groups in 2007 and 2008. Data on this novel course were collected through participant observation, team self-assessment and questionnaires. This paper reports favourable results for the effectiveness of the course design; it discusses the impact of team size and cross-organizational team composition on team performance; and identifies the implications for teaching the front end of innovation. [source] APPLICATION OF DISCRETE MODELING APPROACH TO FLUIDIZED BED YEAST DRYINGJOURNAL OF FOOD PROCESS ENGINEERING, Issue 2010F. DEBASTE ABSTRACT Yeast drying is widely used to ease transport and conservation. In this work, baker's yeast drying in fluidized bed is modeled using a pore network model. Classical balanced equations at the reactor scale are coupled with the pore network for the grain, which takes into account diffusion in the gas phase, transport by liquid film in partially saturated region and pressure gradient effects in the liquid phase. The porous structure to be applied in the model is obtained using environmental scanning electron microscopy. Simulations are validated on a thermogravimetric analysis experiment. The model is then applied to fluidized bed drying for which experimental results obtained on a laboratory pilot are available. Finally, the model results are compared to those of a simplified receding front model. PRACTICAL APPLICATIONS The presented model allows simulation of Saccharomyces cerevisiae fluidized bed drying. Taking into account transport phenomena in the grain offers the opportunity to predict drying rate without the use of a desorption isotherm. Moreover, the model predicts roughly the critical humidity. Therefore, the model can be used for scale-up, design and optimization of dryer including the effect of changes in yeast granulation. [source] Engineered Pyranose 2-Oxidase: Efficiently Turning Sugars into Electrical EnergyELECTROANALYSIS, Issue 7-8 2010Oliver Spadiut Abstract Due to the recent interest in enzymatic biofuel cells (BFCs), sugar oxidizing enzymes other than the commonly used glucose oxidase are gaining more importance as possible bioelements of implantable microscale-devices, which can, for example, be used in biosensors and pacemakers. In this study we used rational and semi-rational protein design to improve the catalytic activity of the enzyme pyranose 2-oxidase (P2Ox) with its alternative soluble electron acceptors 1,4-benzoquinone and ferricenium ion, which can serve as electron mediators, to possibly boost the power output of enzymatic BFCs. Using a screening assay based on 96-well plates, we identified the variant H450G, which showed lower KM and higher kcat values for both 1,4-benzoquinone and ferricenium ion compared to the wild-type enzyme, when either D -glucose or D -galactose were used as saturating electron donors. Besides this variant, we analyzed the variants V546C and T169G/V546C for their possible application in enzymatic BFCs. The results obtained in homogeneous solution were compared with those obtained when P2Ox was immobilized on the surface of graphite electrodes and either "wired" to an osmium redox polymer or using soluble 1,4-benzoquinone as mediator. According to the spectrophotometrically determined kinetic constants, the possible energy output, measured in flow injection analysis experiments with these variants, increased up to 4-fold compared to systems employing the wild-type enzyme. [source] Identification of plasma membrane autoantigens in autoimmune hepatitis type 1 using a proteomics tool,,HEPATOLOGY, Issue 3 2008Fatima Tahiri Autoimmune hepatitis (AIH) is a liver disease with circulating autoantibodies predominantly directed against widely held cellular components. Because AIH is a liver-specific disease, autoantibodies against plasma membrane antigens may be involved in its pathogenesis and have been reported; however, no definite identification has been described. We thus investigated the fine specificity of anti-hepatocyte plasma membrane autoantibodies in type 1 AIH (AIH-1) using a proteomic tool. A plasma membrane,enriched fraction was validated using enzymatic activity and western blot analysis experiments. Sera from AIH-1 patients (n = 65) and from 90 controls, that is, healthy blood donors (n = 40) and patients with systemic diseases (n = 20) or other liver diseases (n = 30), were studied by immunoblot performed with plasma membrane proteins resolved by either sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) or 2-dimensional (2D) electrophoresis. Proteins contained in the immunoreactive spots were identified by sequences provided by ion-trap mass spectrometry. Hepatocytes probed with sera were also studied using confocal immunofluorescence and immunoelectron microscopy. The more prominent bands stained by patient sera were located at 38 kDa, 48, 50, 52 kDa, 62 kDa, 70 kDa, and a 95-kDa double band. Six proteins with known potential plasma membrane expression were identified: liver arginase (38 kDa), cytokeratins (CK) 8 and 18 (48-52 kDa), heat shock proteins (HSP) of 60, 70, 90 kDa, and valosin-containing protein (VCP) of 92 kDa. The presence of anti-membrane antibodies was confirmed by immunofluorescence and immunoelectron microscopy. Conclusion: Overall, our data demonstrate that liver arginase, CK 8/18, HSP 60, HSP 70, HSP 90, and VCP represent potential candidate targets on liver membrane for autoantibodies in AIH-1. (HEPATOLOGY 2008;47:937,948.) [source] Fuzzy information granules in time series dataINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 7 2004Michael R. Berthold Often, it is desirable to represent a set of time series through typical shapes in order to detect common patterns. The algorithm presented here compares pieces of a different time series in order to find such similar shapes. The use of a fuzzy clustering technique based on fuzzy c-means allows us to detect shapes that belong to a certain group of typical shapes with a degree of membership. Modifications to the original algorithm also allow this matching to be invariant with respect to a scaling of the time series. The algorithm is demonstrated on a widely known set of data taken from the electrocardiogram (ECG) rhythm analysis experiments performed at the Massachusetts Institute of Technology (MIT) laboratories and on data from protein mass spectrography. © 2004 Wiley Periodicals, Inc. [source] The ABC transporter BcatrB from Botrytis cinerea is a determinant of the activity of the phenylpyrrole fungicide fludioxonilPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 5 2001T Vermeulen Abstract This study demonstrates that the ATP-binding cassette (ABC) transporter BcatrB from Botrytis cinerea influences the activity of phenylpyrrole fungicides against the pathogen. This conclusion is based on toxicity assays and northern analysis experiments which show that BcatrB replacement mutants, which do not express the BcatrB gene, show an increased sensitivity to the phenylpyrrole fungicides fludioxonil and fenpiclonil. Mutants overexpressing BcatrB exhibit a decreased sensitivity to these fungicides. In addition, accumulation of fludioxonil by BcatrB replacement mutants was higher than by wild-type isolates. For mutants overexpressing BcatrB the reverse was observed. Additional ABC and major facilitator superfamily (MFS) transporter genes were identified in an expressed sequence tag (EST) database, suggesting that B cinerea has gene families of ABC and MFS transporters. Corresponding fragments of ten ABC (BcatrC,BcatrN) and three MFS transporter genes (Bcmfs1,4) were cloned and characterised. Fludioxonil affected the transcript level of some members of these gene families in germlings during a short treatment with the fungicide at sub-lethal concentrations. Hence, other ABC and MFS transporters may affect the activity of phenylpyrrole fungicides as well. Other fungicides such as the anilinopyrimidine fungicide cyprodinil, the azole fungicide tebuconazole, the dicarboximide fungicide iprodione and the strobilurin fungicide trifloxystrobin also induced transcription of some of the ABC and MFS transporter genes identified. Therefore, we propose that various ABC and MFS transporters function in protection of the fungus against fungicides and are involved in multi-drug resistance development. © 2001 Society of Chemical Industry [source] Study of the modification of the properties of (PP/EPR) blends with a view to preserving natural resources when elaborating new formulation and recycling polymersPOLYMER COMPOSITES, Issue 6 2009Nizar Mnif The aim of the present work is to study how CaCO3, very abundant on earth, can be blended with polypropylene/ethylene propylene rubber (PP/EPR) either to preserve natural resources when elaborating virgin formulations or to simulate mixtures of waste made of CaCO3 filled PP with PP/EPR which could result from end-of-life-vehicles (ELV). The article focuses on the studies of PP/EPR blends, used in the manufacture of automobile fenders, in the presence of nano-CaCO3 and compatibilizers. Blends of various compositions (with and without compatibilizer and nanoparticles) were prepared using a corotating twin-screw extruder. The results were compared with the ones presented by a commercial (PP/EPR) blend. The experiments included mechanical tests, differential scanning calorimetry, scanning electron microscopy, and dynamic mechanical analysis experiments. The presence of the compatibilizers in the (PP/EPR) blends decreases the size of elastomer particles, improves the adherence to the interface and improves the mechanical properties. The nano-CaCO3 would also seem to act as a nucleating agent in the PP/EPR matrix; it increases the cristallinity and the Young modulus of the blends. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers [source] Determination of agrochemical compounds in soya plants by imaging matrix-assisted laser desorption/ionisation mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 18 2005Alexander K. Mullen Detection and imaging of the herbicide mesotrione (2-(4-mesyl-2-nitrobenzoyl)cyclohexane-1,3-dione) and the fungicide azoxystrobin (methyl (E)-2-{2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy]phenyl}-3-methoxyacrylate), on the surface of the soya leaf, and the detection and imaging of azoxystrobin inside the stem of the soya plant, have been achieved using matrix-assisted laser desorption/ionisation quadrupole time-of-flight mass spectrometry. In leaf analysis experiments, the two pesticides were deposited onto the surface of individual soya leaves on growing plants. The soya leaves were removed and prepared for direct and indirect (following blotting onto matrix-coated cellulose membranes) imaging analysis at different periods after initial pesticide application. In stem analysis experiments, azoxystrobin was added to the nutrient solution of a soya plant growing in a hydroponics system. The plant was left for 48,h, and then horizontal and vertical stem sections were prepared for direct imaging analysis. The images obtained demonstrate the applicability of MALDI imaging to the detection and imaging of small organic compounds in plant tissue and further extend the analytical repertoire of the versatile MALDI technique. Copyright © 2005 John Wiley & Sons, Ltd. [source] Background error covariance functions for vector wind analyses using Doppler-radar radial-velocity observationsTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 621C 2006Qin Xu Abstract A two-dimensional form of cross-covariance function between the radar radial- and tangential-components (with respect to the direction of radar beam) of background wind errors is derived. Like the previously derived auto-covariance function for the radial component, this cross-covariance function is homogeneous but non-isotropic in the horizontal. The auto- and cross-covariance functions are used with the statistical interpolation technique to perform a vector wind analysis from Doppler radial-velocity observations on a conical surface of low-elevation radar-scans. The structures of the two covariance functions are compared and interpreted in terms of the influence of a single-point radial-velocity observation on the analysed vector wind field. The utility and value of these covariance functions are demonstrated through analysis experiments that use either simulated radial-velocity data from idealized flows or real radar observations. The results of the statistical interpolation scheme utilizing the proposed covariance functions are shown to be superior to the results of traditional VAD technique. The proposed technique can actually be considered a generalization of the traditional VAD technique. Copyright © 2006 Royal Meteorological Society [source] An error analysis of radiance and suboptimal retrieval assimilationTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 565 2000J. Joiner Abstract One of the outstanding problems in data assimilation has been, and continues to be, how best to utilize satellite data while balancing the trade-off between accuracy and computational cost. A number of weather-prediction centres have recently achieved remarkable success in improving their forecast skill by changing the method in which satellite data are assimilated into the forecast model from the traditional approach of assimilating retrieved products to the direct assimilation of radiances in a variational framework. Although there are. clear theoretical advantages to the direct radiance-assimilation approach, it is not obvious at all to what extent the improvements that have been obtained so far can be attributed to the change in methodology or to various technical aspects of the implementation. The central question we address here is: how much improvement can we expect from assimilating radiances rather than retrievals, all other things being equal? We compare the two approaches in a simplified theoretical framework. Direct radiance analysis is optimal in this idealized context, while the traditional method of assimilating retrievals is suboptimal because it ignores the cross-covariances between background errors and retrieval errors. We show that interactive retrieval analysis (where the same background used for assimilation is also used in the retrieval step) is equivalent to direct assimilation of radiances with suboptimal analysis weights. We illustrate and extend these theoretical arguments with several one-dimensional analysis experiments, where we estimate vertical atmospheric profiles using simulated data from temperature sounding channels of both the High-resolution InfraRed Sounder 2 (HIRS2) and the future Atmospheric InfraRed Sounder (AIRS). In the case of non-interactive retrievals the results depend very much on the quality of the background information used for the retrieval step. In all cases, the impact of the choice of analysis method is dwarfed by the effect of changing some of the experimental parameters that control the simulated error characteristics of the data and the retrieval background. [source] | ||||||||||