21,850 research outputs found
Study of methods for the improvement of bacterial transport media
A series of 500 transport media recipes was tested for ability to hold pure cultures of Streptococcus equisimilus, Corynebacterium equi, Neisseria perflava, and Haemophilus parainfluenzae for 21 days. Stuart Medium Base with 0.4% agar was used as the control medium for this and the other experiments in the investigation. At the end of the holding period inoculated transport media were quantitatively assayed, and the control media were assayed immediately after inoculation. Three vials of each medium were inoculated with an organism, and each vial's medium was diluted and spread on duplicate plates. Assay media for this experiment included Brain Heart Infusion,(BHIA) Tryptic Soy Agar, and BHIA with 1% Isovitalex enrichment
Bacteria classification using Cyranose 320 electronic nose
Background
An electronic nose (e-nose), the Cyrano Sciences' Cyranose 320, comprising an array of thirty-two polymer carbon black composite sensors has been used to identify six species of bacteria responsible for eye infections when present at a range of concentrations in saline solutions. Readings were taken from the headspace of the samples by manually introducing the portable e-nose system into a sterile glass containing a fixed volume of bacteria in suspension. Gathered data were a very complex mixture of different chemical compounds.
Method
Linear Principal Component Analysis (PCA) method was able to classify four classes of bacteria out of six classes though in reality other two classes were not better evident from PCA analysis and we got 74% classification accuracy from PCA. An innovative data clustering approach was investigated for these bacteria data by combining the 3-dimensional scatter plot, Fuzzy C Means (FCM) and Self Organizing Map (SOM) network. Using these three data clustering algorithms simultaneously better 'classification' of six eye bacteria classes were represented. Then three supervised classifiers, namely Multi Layer Perceptron (MLP), Probabilistic Neural network (PNN) and Radial basis function network (RBF), were used to classify the six bacteria classes.
Results
A [6 × 1] SOM network gave 96% accuracy for bacteria classification which was best accuracy. A comparative evaluation of the classifiers was conducted for this application. The best results suggest that we are able to predict six classes of bacteria with up to 98% accuracy with the application of the RBF network.
Conclusion
This type of bacteria data analysis and feature extraction is very difficult. But we can conclude that this combined use of three nonlinear methods can solve the feature extraction problem with very complex data and enhance the performance of Cyranose 320
Laboratory studies in ultraviolet solar physics
The research activity comprised the measurement of basic atomic processes and parameters which relate directly to the interpretation of solar ultraviolet observations and to the development of comprehensive models of the component structures of the solar atmosphere. The research was specifically directed towards providing the relevant atomic data needed to perform and to improve solar diagnostic techniques which probe active and quiet portions of the solar chromosphere, the transition zone, the inner corona, and the solar wind acceleration regions of the extended corona. The accuracy with which the physical conditions in these structures can be determined depends directly on the accuracy and completeness of the atomic and molecular data. These laboratory data are used to support the analysis programs of past and current solar observations (e.g., the Orbiting solar Observatories, the Solar Maximum Mission, the Skylab Apollo Telescope Mount, and the Naval Research Laboratory's rocket-borne High Resolution Telescope and Spectrograph). In addition, we attempted to anticipate the needs of future space-borne solar studies such as from the joint ESA/NASA Solar and Heliospheric Observatory (SOHO) spacecraft. Our laboratory activities stressed two categories of study: (1) the measurement of absolute rate coefficients for dielectronic recombination and electron impact excitation; and (2) the measurement of atomic transition probabilities for solar density diagnostics. A brief summary of the research activity is provided
Conceptual design and analysis of a large antenna utilizing electrostatic membrane management
Conceptual designs and associated technologies for deployment 100 m class radiometer antennas were developed. An electrostatically suspended and controlled membrane mirror and the supporting structure are discussed. The integrated spacecraft including STS cargo bay stowage and development were analyzed. An antenna performance evaluation was performed as a measure of the quality of the membrane/spacecraft when used as a radiometer in the 1 GHz to 5 GHz region. Several related LSS structural dynamic models differing by their stiffness property (and therefore, lowest modal frequencies) are reported. Control system whose complexity varies inversely with increasing modal frequency regimes are also reported. Interactive computer-aided-design software is discussed
A Web/Grid Services Approach for Integration of Virtual Clinical & Research Environments
Clinicans have responsibilities for audit and research, often participating in projects with basic scientist colleagues. Our work in a regional teaching hospital setting involves collaboration with the medical school computer services and builds upon work developed in computer science department as part of the Collaborative Orthopaedic Research Environment (CORE) project[1]. This has established a pilot study for proof of concept work. Users are mapped to a personal profile implemented using XML and a service oriented architecture (SOA)[2,3]. This bridges the e-Health and e-Science domains, addressing some of the basic questions of security and uptake
Low cycle fatigue behaviour of wire arc additively manufactured ER70S-6 steel
Wire arc additive manufacturing (WAAM) is a method of 3D printing that is well suited to the cost-sensitive construction industry. Fundamental test data on the mechanical properties of WAAM materials, especially under cyclic loading, are however lacking. To bridge this gap, an experimental study into the low cycle fatigue (LCF) behaviour of WAAM ER70S-6 steel has been conducted and is presented herein. Following quasi-static mechanical and geometric characterisation, a series of as-built and machined coupons was tested in different directions relative to the print layer orientation (θ = 0°, 45° and 90°) under constant amplitude LCF loading, covering a range of strain amplitudes from ±0.2% to ±2.0%. Fractographic analysis of the tested coupons was also performed to assess their failure mechanisms. On the basis of the experimental results, strain-life relationships and cyclic stress-strain curves were derived. The geometric undulations of the as-built coupons resulted in a weakening in the LCF properties, and the weakening effect increased with the loading angle θ and strain amplitude. The cyclic hardening/softening response of the WAAM material varied with the imposed strain amplitudes, while significant non-Masing behaviour was observed
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