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81.
Jakub Horak 《Journal of Insect Conservation》2014,18(4):637-642
Semi-natural habitats are currently one of the most important environments for many taxa. The main aim of this study was to discover how diurnal butterflies (Lepidoptera) and flower-visiting beetles (Coleoptera) respond to the environment of traditional fruit orchards. In total, 25 orchards were studied in the rural-agricultural landscape in the Czech Republic. Both study taxa were sampled using timed survey walks in 2010. Seven variables in two environmental categories (patch and geography) were evaluated with respect to the species richness of the studied taxa using partial regression, hierarchical partitioning and generalized linear modeling of the best selected variables. Butterflies were highly influenced at a patch level. An increased number of flowering plants, as a reflection of nectar sources for adults, significantly explained a high level of variability, both alone and via interaction with other studied variables. Beetles were influenced by patch and geography to the same degree, although altitude (as a reflection of geographical heterogeneity) significantly negatively explained the highest level of variability. The results indicate that diurnal butterflies and flower-visiting beetles as insect taxa with similar habitat requirements respond differently in heterogeneous environments of traditional fruit orchards. They also indicate the need for multi-taxa studies, even in marginal ecosystems of recent landscapes. 相似文献
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Monika Holubova Martin Leba Markéta Sedmikova Luca Vannucci Vratislav Horak 《In vitro cellular & developmental biology. Animal》2012,48(10):610-618
Establishment of new animal models using selected cell lines with different behaviour is very important for cancer investigations. In this study, we describe three morphologically distinct rat sarcoma clones??C4, C7 and D6??isolated from the R5-28 cell line. Cells of all clones expressed vimentin, fibronectin, laminin, collagen IV and matrix metalloproteinases 2 and 9. However, desmin, cytokeratins 8 and 18, ZO-1 and desmoplakins I and II were not detected. Significant proliferative capacity was documented by proliferating cell nuclear antigen expression and BrdU positivity. Karyotype of the C4, C7 and D6 cells greatly differed from diploid chromosome number of normal rat somatic cells. High expression of three cytokines??monocyte chemoattractant protein 1, tissue inhibitor of metalloproteinases 1 and vascular endothelial growth factor??was observed in all three clones. However, they varied in concentration of chemokines associated with neutrophil migration and activation??cytokine induced neutrophil chemoattractant 2 and lipopolysaccharide induced CXC chemokine. The C4 clone showed spontaneous tumour regression in vivo that was associated with significant changes in lymphocyte subpopulations. 相似文献
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Benjamin Stich Bettina IG Haussmann Raj Pasam Sankalp Bhosale C Tom Hash Albrecht E Melchinger Heiko K Parzies 《BMC plant biology》2010,10(1):216
Background
The distribution area of pearl millet in West and Central Africa (WCA) harbours a wide range of climatic and environmental conditions as well as diverse farmer preferences and pearl millet utilization habits which have the potential to lead to local adaptation and thereby to population structure. The objectives of our research were to (i) assess the geographical distribution of genetic diversity in pearl millet inbreds derived from landraces, (ii) assess the population structure of pearl millet from WCA, and (iii) identify those geographical parameters and environmental factors from the location at which landraces were sampled, as well as those phenotypic traits that may have affected or led to this population structure. Our study was based on a set of 145 inbred lines derived from 122 different pearl millet landraces from WCA. 相似文献89.
In order to determine the type of somatosensory information for postural control that is most affected by neuropathy, we compared the relative effects of three methods of sway-referencing the surface in a group of subjects with profound loss of somatosensory function associated with sensory polyneuropathy from diabetes with age-matched control subjects. Sway-referencing disrupted somatosensory feedback for postural control by servo-controlling the dorsi- and plantar-flexion rotation of the support surface in proportion to anterior-posterior excursion of (1) ankle angle, (2) center of body mass (CoM) angle or (3) filtered center of pressure (CoP). Postural sway in subjects with somatosensory loss was significantly larger than normal on a firm surface but not on the sway-referenced surfaces, suggesting that sway-referencing disrupts somatosensory information for postural control already disrupted by neuropathy. Control subjects standing on any sway-referenced surface swayed significantly more than neuropathy subjects who stood on a firm surface, suggesting that sway-referencing disrupts more somatosensory information than disrupted by severe neuropathy. CoP sway-referencing was less sensitive than ankle or CoM sway-referencing for distinguishing postural sway in subjects with somatosensory loss from age-matched control subjects. Given that filtered CoP sway-referencing disrupts the ability to utilize somatosensory information related to surface reactive force to a greater extent than the other two methods of sway-referencing, then these results support the hypothesis that subjects with diabetic peripheral neuropathy have lost more CoP information, than ankle or CoM angle information, for controlling postural sway in stance. 相似文献
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Stepping in place on a rotating platform for a period of 15 minutes induces an adaptive response, podokinetic after-rotation (PKAR), which causes a blindfolded individual to inadvertently rotate when attempting to step in place on the floor. The purpose of this investigation was to determine whether lower extremity load receptors were involved in this adaptation. As load receptor input is critical for locomotion, we hypothesized that manipulating load via body weight support (BWS) would influence PKAR. Eleven healthy female volunteers performed 15 minutes of stepping in place on a rotating treadmill (stimulation), followed by 10 minutes of stepping in place (response) without vision on a stationary surface. Response and stimulation periods were with 50% body weight support (BWS) and without body weight support (NoBWS) in all four possible combinations (BWS-BWS, NoBWS-NoBWS, BWS-NoBWS, and NoBWS-BWS). Conditions were randomly assigned to all subjects and performed on four separate occasions at least 48 hr apart. During the 10-min PKAR response period, trunk angular velocity was calculated and plotted versus time, and exponential models were applied to the data to obtain curve-fit parameters for each condition. Despite the manipulations of BWS, no significant differences were found for any parameter value (p = 0.13–0.98). BWS applied during stimulation only, response only, or during both stimulation and response does not appear to influence PKAR. This suggests that load receptors may not play a critical role in mediating adaptive changes in locomotor trajectory control in response to walking on a rotating surface. 相似文献