Performance assessment of onboard and scene-based methods for Airborne Prism Experiment spectral characterization

Accurate spectral calibration of airborne and spaceborne imaging spectrometers is essential for proper preprocessing and scientific exploitation of high spectral resolution measurements of the land and atmosphere. A systematic performance assessment of onboard and scene-based methods for in-flight monitoring of instrument spectral calibration is presented for the first time in this paper. Onboard and ground imaging data were collected at several flight altitudes using the Airborne Prism Experiment (APEX) imaging spectrometer. APEX is equipped with an in-flight characterization (IFC) facility allowing the evaluation of radiometric, spectral, and geometric system properties, both in-flight and on-ground for the full field of view. Atmospheric and onboard filter spectral features present in at-sensor radiances are compared with the same features in reference transmittances convolved to varying instrument spectral configurations. A spectrum-matching algorithm, taking advantage of the high sensitivity of measurements around sharp spectral features toward spectrometer spectral performance, is used to retrieve channel center wavelength and bandwidth parameters. Results showed good agreement between spectral parameters estimated using onboard IFC and ground imaging data. The average difference between estimates obtained using the O(2) and H(2)O features and those obtained using the corresponding filter features amounted to about 0.3 nm (0.05 of a spectral pixel). A deviation from the nominal laboratory instrument spectral calibration and an altitude-dependent performance was additionally identified. The relatively good agreement between estimates obtained by the two approaches in similar spectral windows suggests they can be used in a complementary fashion: while the method relying on atmospheric features can be applied without the need for dedicated calibration acquisitions, the IFC allows assessment at user-selectable wavelength positions by custom filters as well as for the system on-ground.     

From bulk to single-cell classification of the filamentous growing Streptomyces bacteria by means of Raman spectroscopy

Classification of Raman spectra recorded from single cells is commonly applied to bacteria that exhibit small sizes of approximately 1 to 2 μm. Here, we study the possibility to adopt this classification approach to filamentous bacteria of the genus Streptomyces. The hyphae can reach extensive lengths of up to 35 μm, which can correspond to a single cell identified in light microscopy. The classification of Raman bulk spectra will be demonstrated. Here, ultraviolet resonance Raman (UV RR) spectroscopy is chosen to classify six Streptomyces species by the application of a tree-like classifier. For each knot of the hierarchical classifier, estimated classification accuracies of over 94% are accomplished. In contrast to the classification of bulk spectra, the classification of single-cell spectra requires a homogenous substance distribution within the cell. Consequently, the bacterial cell chemistry can be represented by one individual spectrum. This requirement is not fulfilled when different spectra are processed from different locations within the cell. Bacteria of the investigated genus Streptomyces exhibit, besides the normal bacterial spectra, lipid-rich spectra. The occurrence of lipid enrichment depends on culture age and nutrition availability. With this study, we investigate the cell substance distribution, especially of lipid-rich fractions. The classification utilizing a tree-like classifier is also applied to the Streptomyces single-cell spectra, resulting in classification accuracies between 80 and 93% for the investigated Streptomyces species.     

Physicochemical and functional properties of a protein isolate produced from safflower (Carthamus tinctorius L.) meal by ultrafiltration

BACKGROUND: The protein isolate obtained from safflower meal by aqueous extraction and ultrafiltration was evaluated for its physicochemical and functional properties. RESULTS: Protein, ash and moisture contents of the safflower protein isolate were 901, 51 and 45 g kg^?1 respectively. Its water and oil absorption capacities were 2.22 mL H₂O g^?1 protein and 2.77 mL oil g^?1 protein respectively. Least gelation concentration was 20 g kg^?1 at pH 2, 6, 8 and 10 but 100 g kg^?1 at pH 4. Emulsifying properties were also affected by the pH: emulsifying activity and emulsion stability at pH 6 were 82.5 and 100% respectively. The highest foaming capacity (126%) occurred at pH 2; however, it increased by 104% with the addition of 0.25 g glucose g^?1 protein to the foam system. CONCLUSION: In the light of its functional properties found in this study, safflower protein isolate produced by ultrafiltration is recommended for use as an ingredient in food products such as salad dressing, meat products, mayonnaise, cakes, ice cream and desserts. Copyright © 2010 Society of Chemical Industry     

Lack of Pervasiveness of the Underconfidence-With-Practice Effect: Boundary Conditions and an Explanation Via Anchoring.

The authors investigated whether underconfidence in judgments of learning (JOLs) is pervasive across multiple study-test trials as suggested by A. Koriat, L. Sheffer, and H. Ma'ayan (2002) or whether underconfidence with practice (UWP) might be a kind of anchoring-and-adjustment effect, such that the occurrence or nonoccurrence of the UWP effect depends on whether recall is above a psychological anchor. Participants studied normatively difficult items or normatively easy items and made immediate JOLs or delayed JOLs. The UWP effect occurred for easy items, but for difficult items an overconfidence-with-practice (OWP) effect occurred for delayed JOLs and no bias occurred for immediate JOLs. The systematic occurrence of all 3 outcomes establishes boundary conditions for the UWP effect and confirms the hypothesis that underconfidence (or the lack thereof) may arise at least in part from an anchoring-and-adjustment mechanism. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Species richness, structural diversity and species composition in meadows created by visitors of a botanical garden in Switzerland

Biodiversity is an increasingly important criterion in designing ecological compensation areas and urban green areas. However, little is known about how important biodiversity is to the general public. This paper presents the results of two complementary studies investigating the meadow preferences of visitors to a botanical garden in Switzerland. In the first study, 152 people were asked to create their own favourite meadow patch by selecting 25 out of 779 local wild plants (54 species) that were displayed in flowerpots. In the second study, 143 people were asked with the help of a written questionnaire to imagine a bare piece of land the size of 100 m × 100 m close to their place of living and mentally create the meadow of their dreams. In both cases, study participants assembled meadows that were species-rich and rich in structural diversity (expressed by plant height and leaf forms). Moreover, they explicitly stated diversity as their main assemblage criterion. Although study participants favoured plants with large or colourful flowers, only a third of all plants in the meadows created with real plants were flowering and in people's imagined meadows grasses were frequently included, indicating that people like diverse meadows consisting of a green matrix with some colourful flowers.     

Stability of the contractile assembly and Ca2+-activated tension in adenovirus infected adult cardiac myocytes

Rats were given suction lesions of the presumptive frontal cortex on embryonic day 18 (E18) and subsequently tested, as adults, on tests of spatial navigation (Morris water task, radial arm maze), motor tasks (Whishaw reaching task, beam walking), and locomotor activity. Frontal cortical lesions at E18 affected cerebral morphogenesis, producing unusual morphological structures including abnormal patches of neurons in the cortex and white matter as well as neuronal bridges between the hemispheres. A small sample of E18 operates also had hydrocephaly. The animals with E18 lesions without hydrocephalus were behaviorally indistinguishable from littermate controls. The results demonstrate that animals with focal lesions of the presumptive frontal cortex have gross abnormalities in cerebral morphology but the lesions leave the functions normally subserved by the frontal cortex in adult rats unaffected. The results are discussed in the context of a hypothesis regarding the optimal times for functional recovery from cortical injury.