86 resultados para quantitative proteomics


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Perhaps one of the most important end products of a dance work is how it  effects its observers (typically its audience, but also the dancers and choreographers). Of the many ways of discussing and analysing dance, one
approach in its infancy is quantification. Our research involves combining continuous response techniques and human response methods to see if we can tease out relationships between continuous, quantitative evaluative responses and the more qualitative choreographer intentions. The aim of this paper is to describe how evaluative responses can be quantified at all, then how they can be related to an unfolding dance work, and finally, how we can isolate ‘meaningful’ or ‘significant’ or ‘reliable’ evaluations of a dance work from those which are no more than a spurious set of not-very-useful numbers presented under the guise of a valid assessment.

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Restoration of native vegetation is required in many regions of the world, but determining priority locations for revegetation is a complex problem. We consider the problem of determining spatial and temporal priorities for revegetation to maximize habitat for 62 bird species within a heavily cleared agricultural region, 11 000 km2 in area. We show how a reserve-selection framework can be applied to a complex, large-scale restoration-planning problem to account for multi-species objectives and connectivity requirements at a spatial extent and resolution relevant to management. Our approach explicitly accounts for time lags in planting and development of habitat resources, which is intended to avoid future population bottlenecks caused by delayed provision of critical resources, such as tree hollows. We coupled species-specific models of expected habitat quality and fragmentation effects with the dynamics of habitat suitability following replanting to produce species-specific maps for future times. Spatial priorities for restoration were determined by ranking locations (150-m grid cells) by their expected contribution to species habitat through time using the conservation planning tool, ‘‘Zonation.’’ We evaluated solutions by calculating expected trajectories of habitat availability for each species. We produced a spatially explicit revegetation schedule for the region that resulted in a balanced increase in habitat for all species. Priority areas for revegetation generally were clustered around existing vegetation, although not always. Areas on richer soils and with high rainfall were more highly ranked, reflecting their potential to support high-quality habitats that have been disproportionately cleared for agriculture. Accounting for delayed development of habitat resources altered the rank-order of locations in the derived revegetation plan and led to improved expected outcomes for fragmentation-sensitive species. This work demonstrates the potential for systematic restoration planning at large scales that accounts for multiple objectives, which is urgently needed by land and natural resource managers.

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Combined effects of hydrogen and air flow rates on the peak response of selected neutral lipid classes (triacylglycerol, diacylglycerol, monoacylglycerol, free fatty acids, and ethyl esters) were studied to optimize and calibrate the Iatroscan Mk-6s Chromarod system for the qualitative and quantitative analysis of lipid classes by thin-layer chromatography (TLC) with flame ionization detection in fish oil during the transesterification process. Air flow rate of 2 L/min, hydrogen flow rate of 150-160 mL/min, and scan rate of 30 s/rod were found to be the optimum conditions. All samples were also analyzed by high performance liquid chromatography (HPLC) with evaporative light scattering detection. Quantitative results obtained by TLC with the flame ionization detection method were comparable to those obtained from HPLC with evaporative light scattering detection.

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In order to determine the range of Australian perceptions on new venture creation at the end of the decade of the 1980s, and in particular attitudes towards government involvement in fostering entrepreneurship, a major quantitative study was conducted. The survey involved more than 1500 Australians in face-to-face interviews (300 in each mainland capital city) chosen on a random basis.

An analysis of the data provides an assessment of the Australian general public&s perceptions in three key areas: their understanding of the word 'entrepreneur' their rating of importance of new venture creation; their belief in government involvement in fostering new venture creation.

It is believed to be the first study attempting to quantify an entire nation&s perceptions in three areas vital to creators of national economic and industry policies.

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Background/Aim: The study investigated the relationship between indices of adiposity measured by peripheral quantitative computed tomography (pQCT) and dual-energy X-ray absorptiometry (DXA) in pre-pubertal children.

Subjects and methods: DXA-derived per cent body fat (%BF) was measured in 284 boys and 288 girls, aged 7–10 years. Cross-sections of the forearm (n=427) and lower leg (n=560) were obtained by pQCT to measure total cross-sectional area of the limb (Total CSA), Muscle CSA, Fat CSA, %Fat CSA (Fat CSA/Total CSA×100) and muscle density.

Results: Peripheral QCT-derived %Fat CSA in the forearm and lower leg correlated strongly with DXA-derived %BF (r=0.83–0.89, p<0.01) in both boys and girls. However, forearm and lower leg %Fat CSA were higher than whole body %BF by 5% and 10%, respectively. A better prediction of whole-body %BF was achieved by including %Fat CSA, muscle density and height into a hierarchical regression model. Using sex-specific regression equations, 87.7% of the boys and 83.7% of the girls had a predicted %BF within 3% units of the %BF obtained by DXA.

Conclusion:
In pre-pubertal children, pQCT measures of adiposity are strongly associated with whole-body per cent body fat. This reproducible method could be an alternative technique to estimate body composition in this population.

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The chromatographic capacity factors (log k‘) for 32 structurally diverse drugs were determined by high performance liquid chromatography (HPLC) on a stationary phase composed of phospholipids, the so-called immobilized artificial membrane (IAM). In addition, quantitative structure-retention relationships (QSRR) were developed in order to explain the dependence of retention on the chemical structure of the neutral, acidic, and basic drugs considered in this study. The obtained retention data were modeled by means of multiple regression analysis (MLR) and partial least squares (PLS) techniques. The structures of the compounds under study were characterized by means of calculated physicochemical properties and several nonempirical descriptors. For the carboxylic compounds included in the analysis, the obtained results suggest that the IAM-retention is governed by hydrophobicity factors followed by electronic effects due to polarizability in second place. Further, from the analysis of the results obtained of two developed quantitative structure-permeability studies for 20 miscellaneous carboxylic compounds, it may be concluded that the balance between polarizability and hydrophobic effects is not the same toward IAM phases and biological membranes. These results suggest that the IAM phases could not be a suitable model in assessing the acid-membrane interactions. However, it is not possible to generalize this observation, and further work in this area needs to be done to obtain a full understanding of the partitioning of carboxylic compounds in biological membranes. For the non-carboxylic compounds included in the analysis, this work shows that the hydrophobic factors are of prime importance for the IAM-retention of these compounds, while the specific polar interactions, such as electron pair donor−acceptor interactions and electrostatic interactions, are also involved, but they are not dominant.

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We describe methods for obtaining a quantitative description of RNA processing at high resolution in budding yeast. As a model gene expression system, we constructed tetON (for induction studies) and tetOFF (for repression, derepression, and RNA degradation studies) yeast strains with a series of reporter genes integrated in the genome under the control of a tetO7 promoter. Reverse transcription and quantitative real-time-PCR (RT-qPCR) methods were adapted to allow the determination of mRNA abundance as the average number of copies per cell in a population. Fluorescence in situ hybridization (FISH) measurements of transcript numbers in individual cells validated the RT-qPCR approach for the average copy-number determination despite the broad distribution of transcript levels within a population of cells. In addition, RT-qPCR was used to distinguish the products of the different steps in splicing of the reporter transcripts, and methods were developed to map and quantify 3′-end cleavage and polyadenylation. This system permits pre-mRNA production, splicing, 3′-end maturation and degradation to be quantitatively monitored with unprecedented kinetic detail, suitable for mathematical modeling. Using this approach, we demonstrate that reporter transcripts are spliced prior to their 3′-end cleavage and polyadenylation, that is, cotranscriptionally.

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The sperm cells of Rhododendron laetum and R. macgregoriae differentiate within the pollen tube about 24 h after germination in vitro. Threedimensional reconstruction shows that the sperm cells are paired together, and both have extensions that link with the tube nucleus, forming a male germ unit. Quantitative analysis shows that the sperm cells in each pair differ significantly in surface area, but not in cell volume nor in numbers of mitochondria or plastids. When isolated from pollen tubes by osmotic shock, the sperm cells became ellipsoidal and surrounded by their own plasma membrane, while a proportion remained in pairs linked by the inner tube plasma membrane. Both generative and sperm cells are visualized in pollen tube preparations by immunofluorescence with anti-tubulin and anti-actin monoclonal antibodies (MAbs) combined with H33258 fluorescence of the nuclei. Video-image processing shows the presence of an axial microtubule cage in the generative cells, and some microtubules are present in the cytoplasmic extensions that clasp the tube nucleus. Following sperm cell division, the extensive phragmoplast between the sperm nuclei is partitioned by the plasma membranes.