バイオおよびライフ・サイエンス

Differences in the metabolite profiles of spinach (Spinacia oleracea L.) leaf in different concentrations of nitrate in the culture solution

Okazaki, Oka, Shinano, Osaki and Takebe (2008) Plant Cell Physiology 49:170-177

Metabolite profiling using gas chromatography-mass spectrometry was used to evaluate the effect of nitrogen levels on spinach tissue, comparing two cultivars that differed in their ability to use nitrogen. SOM analysis using SOMine was used to describe changes in the metabolites of mature spinach leaves. Both PCA and SOM revealed that metabolites could be broadly divided into two types, correlating either positively or negatively with plant nitrogen content. The simple and co-coordinated metabolic stream, containing both general and spinach-specific aspects of plant nitrogen content, will be useful in future research on such topics as the detection of environmental effects on spinach through comprehensive metabolic profiling.

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Sensor combination and chemometric modelling for improved process monitoring in recombinant E. coli fed-batch cultivations

Clementschitsch, Kern, Pötschacher and Bayer, Journal of Biotechnology, 120(2):183-196

The key objective for the optimization of recombinant protein production in bacteria is to maximize the exploitation of the host cell's synthesis potential. Since there are no reliable online-sensors for key variables, it is necessary to relate available online signals to process variables by mathematical models. To improve chemometric modeling of process variables, dielectric spectroscopy and a multi-wavelength online fluorescence sensor for two-dimensional fluorescence spectroscopy were applied in a series of recombinant Escherichia coli fed-batch cultivations, applying two different process operation states. Chemometric modeling of key process variables with two different modeling techniques showed that this sensor combination greatly improved the estimation (i.e., reduce error magnitude) of process variables in recombinant E. coli cultivations, thereby enhancing process monitoring capabilities.

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Individuality of wing patterning in giant honey bees (Apis laboriosa)

Kastberger, Radloff and Kranner (2003) Apidologie 34:311-318

This study investigated whether individual worker bees of a single Apis laboriosa colony can be re-identified by their wing patterns alone. Re-identification was carried out by SOM reclassification and conventional discriminant analysis (DA) using the protocols of recognition (data for training and testing the model are equal or slightly modified by white noise), and prediction (test data are unknown to the model). SOM recognition of wing shaping was found to be more robust than that resulting from DA. The SOM prediction capacity was tested using four test-training data ratios and reached 90% under a two-step reclassification protocol.

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Breeding Rubis cultivars for high anthocyanin content and high antioxidant capacity

McGhie, Hall, Ainge and Mowat (2002) ISHS Acta Horticulturae 585: VIII International Rubus and Ribes Symposium

Anthocyanin content and antioxidant activity from HortResearch Rubus clones were assessed, and a diverse range of anthocyanins and total anthocyanin content was observed. These data could be used to improve commercial production of high-health Rubus crops with significantly higher anthocyanin content and antioxidant capacity than found in existing cultivars.

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Visualization of multiple influences on ocellar flight control in giant honeybees with the data-mining tool Viscovery SOMine

Kastberger and Kranner (2000) Behavior Research Rethods, Instruments & Computers; 32(1):157-68

Viscovery SOMine was used to analyze and visualize multiple influences of the ocellar system on free-flight behavior in giant honeybees. Occlusion of ocelli will affect orienting reactivities in relation to flight target, level of disturbance, and position of the bee in the flight chamber; it will induce phototaxis and make orienting imprecise and dependent on motivational settings. Ocelli permit the adjustment of orienting strategies to environmental demands by enforcing abilities such as centering or flight kinetics and by providing independent control of posture and flight course.

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Visualising spatial patterns in fruit quality and productivity of persimmon orchards using self organising maps

Mowat (2000) Presented at SIRC 2000 - The 12th Annual Colloquium of the Spatial Information Research Centre University of Otago, Dunedin, New Zealand

Fruit quality and productivity datasets, obtained over two seasons from 24 New Zealand persimmon orchards, were analyzed. SOMine was used to construct a 2000 node self organizing map (Kohonen, 1997) from input features (latitude, longitude, and growing region) obtained from each orchard replicate. By overlaying fruit quality and tree productivity attributes as component planes, spatial patterns between orchards could be observed. In addition, climatic data from regional meteorological stations were associated with the map.

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