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141.
Soil Properties and Species Richness of Invertebrates on Afforested Sites after Brown Coal Mining 总被引:1,自引:0,他引:1
Markéta Hendrychová Miroslav Šálek Karel Tajovský Michal Řehoř 《Restoration Ecology》2012,20(5):561-567
Variation in soil properties may influence diversity of invertebrate communities, a crucial component of every ecosystem, and their impact should be considered also in restoration management. Although most spoil heaps have been reclaimed after brown coal mining, some post‐mining sites are left to natural succession. Little is known, however, about the effects of these two fundamentally different approaches on diversity of invertebrates inhabiting these stands. While controlling for habitat characteristics, we analyzed the effects of soil properties on species richness of seven invertebrate groups representing various trophic levels and diverse spatial niches at afforested spoil heaps and adjacent pits managed under these two basic restoration approaches in the North Bohemia Brown Coal Basin (Czech Republic, central Europe). Forty‐seven percentage of 140 invertebrate species occurred on both reclamations and successions, but many were found exclusively on successions (37%) or reclamations (16%). The species richness of various groups was affected by different soil properties either independently of other variables or in interaction with microclimatic conditions or management history. These results imply a need for diverse management approaches in post‐mining areas to support the diversity of invertebrate communities. Technical reclamations with artificial plantations and spontaneous forest development on bare substrate (thus creating mosaics of open patches and afforested stands with different soil deposit materials) were found to be reasonable alternatives to support invertebrate richness on post‐mining forested stands. We conclude that these two approaches should properly be combined in practice. 相似文献
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Background
Early diagnosis of sepsis and its differentiation from the noninfective SIRS is very important in order that treatment can be initiated in a timely and appropriate way. In this study we investigated standard haematological and biochemical parameters and thromboelastography (TEG) in patients who had undergone surgical resection of the oesophagus to find out if changes in any of these parameters could help in early differentiation between SIRS and sepsis development.Methods
We enrolled 43 patients (aged 41?C74?years) of whom 38 were evaluable. Blood samples were obtained on the morning of surgery and then at 24-hour intervals for the next 6?days. Samples were analysed for procalcitonin (PCT), C-reactive protein (CRP), interleukin-6 (IL- 6), aspartate transaminase (AST), alanine transaminase (ALT) , lactate, white blood count (WBC), D-dimers, antithrombin (AT), international normalised ratio (INR), activated partial thromboplastin time (APTT) and parameters of TEG.Results
Significant differences between patients who developed sepsis during this period (9 patients) and SIRS were found in ALT on Day 1, in AST on Days 1?C4, in PCT on Days 2?C6; in CRP on Days 3?C6; in IL-6 on Days 2?C5; in leucocytes on Days 2, 3 and 6; and in D-dimers on Days 2 and 4. Significance values ranged from p?0.0001 to p?0.05.Conclusions
Sequential measurements of ALT, AST, PCT and IL-6 during the early postoperative period can be used for early differentiation of sepsis and postoperative SIRS after oesophagectomy. Among the coagulation parameters measured, only D-dimer concentrations appeared to be helpful in this process. TEG does not seem to be a useful early predictor of sepsis development; however it can be used to differentiate sepsis and SIRS from Day 5 after surgery. 相似文献146.
Highlights? Bacteriophytochrome structure containing photosensory and output transducing domain ? RpBphP1 binds to the cognate repressor RpPpsR2 on illumination with far-red light ? HOS domain is distantly related to Dhp and is essential for binding to the repressor ? Light-induced protomer swapping mechanism between dimers 相似文献
147.
Sykorová B Kuresová G Daskalova S Trcková M Hoyerová K Raimanová I Motyka V Trávnícková A Elliott MC Kamínek M 《Journal of experimental botany》2008,59(2):377-387
The manipulation of cytokinin levels by senescence-regulated expression of the Agrobacterium tumefaciens ipt gene through its control by the Arabidopsis SAG12 (senescence-associated gene 12) promoter is an efficient tool for the prolongation of leaf photosynthetic activity which potentially can affect plant productivity. In the present study, the efficiency of this approach was tested on wheat (Triticum aestivum L.)-a monocarpic plant characterized by a fast switch from vegetative to reproductive growth, and rapid translocation of metabolites from leaves to developing grains after anthesis. When compared with the wild-type (WT) control plants, the SAG12::ipt wheat plants exhibited delayed chlorophyll degradation only when grown under limited nitrogen (N) supply. Ten days after anthesis the content of chlorophyll and bioactive cytokinins of the first (flag) leaf of the transgenic plants was 32% and 65% higher, respectively, than that of the control. There was a progressive increase in nitrate influx and nitrate reductase activity. However, the SAG12::ipt and the WT plants did not show differences in yield-related parameters including number of grains and grain weight. These results suggest that the delay of leaf senescence in wheat also delays the translocation of metabolites from leaves to developing grains, as indicated by higher accumulation of ((15)N-labelled) N in spikes of control compared with transgenic plants prior to anthesis. This delay interferes with the wheat reproductive strategy that is based on a fast programmed translocation of metabolites from the senescing leaves to the reproductive sinks shortly after anthesis. 相似文献
148.
Umannová L Machala M Topinka J Nováková Z Milcová A Kozubík A Vondrácek J 《Mutation research》2008,640(1-2):162-169
Benzo[a]pyrene (BaP) is a ubiquitous environmental pollutant, which may contribute to the development of human cancer. The ultimate carcinogenic BaP metabolite produced by cytochrome P450 enzymes (CYP), such as CYP1A1 and CYP1B1, anti-BaP-7,8-diol-9,10-epoxide, binds covalently to DNA and causes mutations. The levels of various CYP isoforms can be significantly modulated under inflammatory conditions. As the chronic inflammation is known to contribute to carcinogenesis, we investigated interactions of a major proinflammatory cytokine, tumor necrosis factor-alpha (TNF-alpha), and BaP in regulation of the expression of CYP1A1/1B1 and induction of DNA damage in rat liver epithelial WB-F344 cells. TNF-alpha enhanced induction of CYP1B1, while it simultaneously suppressed the BaP-induced CYP1A1 expression. The observed deregulation of CYP1 induction was found to be associated with a significantly enhanced formation of DNA adducts. The elevated DNA damage corresponded with increased phosphorylation of p53 tumor suppressor at Ser-15 residue, enhanced accumulation of cells in the S-phase of cell cycle and potentiation of BaP-induced apoptosis. Inhibition of CYP1B1 by fluoranthene significantly decreased both the formation of DNA adducts and the induction of apoptosis in WB-F344 cells treated with BaP and TNF-alpha, thus suggesting that this isoform might be responsible for genotoxic effects of BaP in nonparenchymal liver cells. Our results seem to indicate that inflammatory conditions might enhance genotoxic effects of carcinogenic polycyclic aromatic hydrocarbons through upregulation of CYP1B1 expression. 相似文献
149.
Differences in AM fungal root colonization between populations of perennial Aster species have genetic reasons 总被引:1,自引:1,他引:0
We tested the hypothesis whether differences between plant populations in root colonization by arbuscular mycorrhizal (AM) fungi could be caused by genetic differentiation between populations. In addition, we investigated whether the response to AM fungi differs between plants from different populations and if it is affected by the soil in which the plants are cultivated. We used Aster amellus, which occurs in fragmented dry grasslands, as a model species and we studied six different populations from two regions, which varied in soil nutrient concentration.We found significant differences in the degree of mycorrhizal colonization of plant roots between regions in the field. To test if these differences were due to phenotypic plasticity or had a genetic basis, we performed a greenhouse experiment. The results suggested that Aster amellus is an obligate mycotrophic plant species with a high dependency upon mycorrhiza. Plant biomass was affected only by soil, and not by population or the interaction between the population and the soil. Mycorrhizal colonization was significantly affected by all three factors (soil, population, interaction of soil and population). Plants from the population originating from the soil with lower nutrient availability developed more mycorrhiza even when grown in soil with higher nutrient availability. The correspondence between mycorrhizal colonization of plants in the field and in both soils in the pot experiment suggests that the observed differences in root colonization have a genetic basis. 相似文献
150.
The structure of pyrenetetrasulfonate intercalated with hydrotalcite, having the formula [Zn0.68Al0.32(OH)2][(C16H6O12S4)0.08 · x H2O], was proposed based on molecular simulations combined with experimental data (X-ray powder diffraction, thermogravimetry).
Calculations were done for samples kept at various relative humidities (0%, 84%, 98%). The appropriate models were selected
from comparison of calculated and measured diffraction patterns. Modelling revealed the arrangement of pyrenetetrasulfonate
anions, and the positions and the amount of water molecules in the interlayer space of the host structure. The results confirmed
a large variability in the arrangement of the guest species. In the sample without water molecules (0% RH), pyrenetetrasulfonate
anions formed a layer at the centre of the interlayer distance. For the sample kept at 84% RH, the anions formed two layers
at the thirds of the interlayer. For the sample kept at 98% RH, the anions became tilted with respect to the layered double
hydroxides (LDH) layers and are less organised. Water molecules were arranged in three distinct planes: one in the middle
and two at the quarters of interlayer distance. The number of water molecules obtained by the modelling basically agrees with
the water content as measured by thermogravimetry.
Figure Pyrenetetrasulfonate was intercalated into hydrotalcite and equilibrated at various relative humidities. Structural analysis
was performed using molecular simulations based on X-ray and thermogravimetric data 相似文献