30 research outputs found

    Morphological diversity of ground beetles (Coleoptera: Carabidae) in Scottish agricultural land

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    The morphospace de®ned by 87 species of ground beetle (Coleoptera: Carabidae) of Scottish non-forested habitats is described with multivariate methods, using 13 linear quantitative measurements of the body, hind legs, eyes and antennae, plus ®ve qualitative characters concerned with body shape, colour, wing development, and pubescence. Relationships between pairs of variables are studied with phylogenetic independent contrasts, using two different taxonomic classi®cations as an approximation to the phylogeny of the group. The ®rst ordination axis of the morphospace was found mainly to re¯ect the positive correlation between length of the antennae and length of the hind legs, the second to re¯ect the width of the head, diameter of the eye and pronotum height, and the third the width of the pronotum and elytra, length of the metatrochanter and width of the metafemur. The principal relationships involving qualitative characters were between colour of the body and legs and shape of the pronotum with ordination axes, wing development with width of the elytra, and pubescence with colour of the legs. Most correlations between quantitative variables, in particular those most in¯uencing the ordination axes of the morphospace, remained signi®cant when measured with phylogenetic independent contrasts using both classi®cations. Independent contrasts comparing qualitative with quantitative variables or ordination axes were onl

    Are Physiologically-Based Pharmacokinetic Models Reporting the Right Cmax? Central Venous Versus Peripheral Sampling Site

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    Physiologically based pharmacokinetic (PBPK) models can over-predict maximum plasma concentrations (C(max)) following intravenous administration. A proposed explanation is that invariably PBPK models report the concentration in the central venous compartment, rather than the site where the samples are drawn. The purpose of this study was to identify and validate potential corrective models based on anatomy and physiology governing the blood supply at the site of sampling and incorporate them into a PBPK platform. Four models were developed and scrutinised for their corrective potential. All assumed the peripheral sampling site concentration could be described by contributions from surrounding tissues and utilised tissue-specific concentration-time profiles reported from the full-PBPK model within the Simcyp Simulator. Predicted concentrations for the peripheral site were compared to the observed C(max). The models results were compared to clinical data for 15 studies over seven compounds (alprazolam, imipramine, metoprolol, midazolam, omeprazole, rosiglitazone and theophylline). The final model utilised tissue concentrations from adipose, skin, muscle and a contribution from artery. Predicted C(max) values considering the central venous compartment can over-predict the observed values up to 10-fold whereas the new sampling site predictions were within 2-fold of observed values. The model was particularly relevant for studies where traditional PBPK models over-predict early time point concentrations. A successful corrective model for C(max) prediction has been developed, subject to further validation. These models can be enrolled as built-up modules into PBPK platforms and potentially account for factors that may affect the initial mixing of the blood at the site of sampling. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1208/s12248-015-9796-7) contains supplementary material, which is available to authorized users

    White matter volume and anisotropy in preterm children: A pilot study of neurocognitive correlates

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    The objectives of this study were to evaluate the differences in whole brain white matter (WM) volume and anisotropy between preterm and term children and to determine the relationships with cognitive outcome. Twenty-five low birth weight (BW), preterm, neurologically normal children between 8.8 and 11.5 y of age were recruited for volumetric and diffusion-tensor magnetic resonance imaging (DTI), together with 13 age-matched term control subjects. Subsequent intelligence quotient (IQ) testing was performed for 21 preterm children within 6 mo of imaging studies. We computed the mean volume and fractional anisotropy (FA) of the whole brain WM and compared the differences between the two groups. Mean WM volume and FA were significantly lower in the preterm group (p = 0.014 and p < 0.001, respectively). Multiple regression analysis found both WM volume and FA to be independent variables significantly affecting full scale IQ (FSIQ) (r = 0.407, p = 0.021 and r = 0.496, p = 0.005, respectively) after adjusting for BW, gestational age (GA), and gender. In the evaluation of the whole brain WM of preterm children, we found that both volume and FA remain reduced at late childhood with both parameters significantly affecting long-term cognitive outcome. © International Pediatrics Research Foundation, Inc. 2007. All Rights Reserved.link_to_subscribed_fulltex

    Aerial seed storage in Melaleuca ericifolia Sm. (Swamp Paperbark): environmental triggers for seed release

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    Aerial seed banks are potentially the main source of sexual recruitment for woody wetland plants. Whilst the importance of soil seed banks for the persistence and recruitment of wetland plants has been examined in many studies, the role of aerial seed banks has been largely neglected. We used seed traps and the seedling emergence technique to quantify the seed rain from aerial seed banks of the Swamp Paperbark Melaleuca ericifolia Sm. (Myrtaceae) in Dowd Morass, a Ramsar-listed, brackish-water wetland in south-eastern Australia. Nine plant species germinated from material collected in seed traps over 2004–2005, but emergents were dominated (80–97%) by M. ericifolia. The mean number of M. ericifolia emergents ranged from <1 to <100 seedlings m−2 day−1, and showed a peak in the summer–autumn period. Regression analysis showed a significant negative correlation (r 2 = 0.738) between the number of M. ericifolia emergents and water depth. Water depth and salinity were negatively correlated (r 2 = 0.819), and increases in the number of M. ericifolia emergents as water levels fell were also associated with high salinities. Increasing air temperature and vapour pressure deficit also stimulated seed release during periods of drying. This study is one of the first to demonstrate the importance of aerial seed banks for sexual recruitment in woody wetland plants and the release of seed in relation to environmental factors. Aerial seed banks warrant consideration alongside soil seed banks for the establishment and long-term survival of woody plants in wetlands
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