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1.
The monophyly of the tribe Oxyptilini and phylogenetic relationships of the genera embraced in this tribe were examined using 171 (75 binary and 96 multistate) characters of adult morphology. The study material included 98 species of 30 genera, representing all previously recognized genera of Oxyptilini, together with the genera Sphenarches, Antarches, Diacrotricha, and Cosmoclostis, four species of Oidaematophorini, three species of Platyptiliini, as well as three and two other species belonging to Pterophorini and Exelastini respectively. Two Agdistis species were used as outgroups. The cladistic analysis resulted in six equally parsimonious trees. A majority of the recovered synapomorphic characters have previously been used in the taxonomy of the subfamily. However, 25 novel characters were found. The monophyly of Oxyptilini was supported, although only with homoplastic characters and low amounts of tree confidence; the genera Capperia, Procapperia, Paracapperia, Oxyptilus, Megalorhipida, and Trichoptilus were found to be nonmonophyletic; Sphenarches and Antarches were recovered as members of Oxyptilini; the two genera Cosmoclostis and Diacrotricha were placed out of Oxyptilini, inside the tribe Pterophorini; and close affinity of the genus Dejongia to Stangeia, Stenodacma, Megalorhipida, Trichoptilus, and Buckleria species was revealed. Four new combinations, Cosmoclostis lanceata (Arenberger) comb. nov. , Nippoptilia regulus (Meyrick) comb. nov. , Capperia tadzhica (Zagulajev) comb. nov. , and Buckleria negotiosus (Meyrick) comb. nov. are proposed; Capperia insomnis Townsend was considered as a senior synonym of Procapperia hackeri Arenberger syn. nov. , Buckleria negotiosus (Meyrick) as a senior synonym of Buckleria vanderwolfi Gielis syn. nov. , and Oxyptilus variegatus Meyrick syn. nov. as a junior synonym of Oxyptilus secutor Meyrick. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 163 , 484–547.  相似文献   
2.
We investigated how leaf hydraulic conductance (Kleaf) of loblolly pine trees is influenced by soil nitrogen amendment (N) in stands subjected to ambient or elevated CO2 concentrations (CO2a and CO2e, respectively). We also examined how Kleaf varies with changes in reference leaf water potential (Ψleaf‐ref) and stomatal conductance (gs‐ref) calculated at vapour pressure deficit, D of 1 kPa. We detected significant reductions in Kleaf caused by N and CO2e, but neither treatment affected pre‐dawn or midday Ψleaf. We also detected a significant CO2e‐induced reduction in gs‐ref and Ψleaf‐ref. Among treatments, the sensitivity of Kleaf to Ψleaf was directly related to a reference Kleaf (Kleaf‐ref computed at Ψleaf‐ref). This liquid‐phase response was reflected in a similar gas‐phase response, with gs sensitivity to D proportional to gs‐ref. Because leaves represented a substantial component of the whole‐tree conductance, reduction in Kleaf under CO2e affected whole‐tree water use by inducing a decline in gs‐ref. The consequences of the acclimation of leaves to the treatments were: (1) trees growing under CO2e controlled morning leaf water status less than CO2a trees resulting in a higher diurnal loss of Kleaf; (2) the effect of CO2e on gs‐ref was manifested only during times of high soil moisture.  相似文献   
3.
1. We studied the patterns of litter decomposition in lake littoral habitats and investigated whether decay rates, as an integrating proxy for environmental conditions in the sediment, would co‐vary with net carbon dioxide (CO2) exchange and methane (CH4) efflux. These gas fluxes are known to be sensitive to environmental conditions. Losses in the mass of cellulose, root, rhizome and moss litter were measured during 2 years in boreal littoral wetlands in Finland and compared with published data on concurrently measured gas fluxes. Four study sites covered a range of sediment types and hydrological conditions. 2. Decomposition was not linearly related to the duration of flooding but depended on sediment type. Readily decomposable litter fractions, such as cellulose and rhizome litter, lost mass at a faster rate in marshes with a longer period of flooding but wide water level fluctuations that hinder establishment of a Sphagnum cover, than in peat‐forming fens. In marshes, the mean first‐year mass losses were 83–99% and 19–62% for cellulose and rhizomes, respectively. In fens, the respective losses were 40–53% and 33%. In the first year, the loss in the mass of the more recalcitrant root litter did not differ between sites (mean 19–30%) and moss litter lost no mass. 3. The estimated first‐year carbon loss from belowground litter was about 0.1–0.3 times ecosystem respiration and roughly similar to net carbon gas (CO2, CH4) efflux, suggesting that vascular plants and recent plant residues contribute substantially to ecosystem release of carbon gases. On the other hand, at least 40% of the mass of the belowground litter remained on a littoral site after the first 2 years of decomposition. Slow decomposition may indicate the accumulation of organic‐rich sediments. The accumulated carbon could explain the excess CO2 release found in most littoral sites. In continuously inundated sites decomposition rates were similar to those in periodically flooded sites, but ecosystem‐atmosphere CO2 exchange fell to close to zero. This discrepancy implies that the released CO2 is dissolved in water and may be exported into the pelagic zone of the lake.  相似文献   
4.
Selective targeting of transfected mesenchymal stem cells (MSCs) carrying specific antioncogenes to the tumor was suggested as a treatment option. Bone morphogenetic protein-2 (BMP2) was shown to inhibit the proliferation and aggressiveness of osteosarcoma (OS) cells. Here, we aimed to assess the homing efficiency of intraperitoneally administered hMSCs transfected with BMP2 to the tumoral site and their effects on OS using an orthotopic xenograft murine model. Orthotopic xenograft murine model of OS in six-week-old female NOD/SCID mice using 143B cells was established. hMSCs transfected with BMP2 (BMP2+hMSC) were used. In vivo experiments performed on four groups of mice that received no treatment, or intraperitoneally administered BMP2, hMSCs, and BMP2+hMSCs. Histopathological and immunohistochemical studies were used to evaluate the pathological identification and to assess the dimensions and necrotic foci of the tumor, the features of lung metastases, and immunostaining against p27, Ki-67, and caspase-3 antibodies. The osteogenic differentiation markers BMP2, BMP4, COL1A1, OPN, OCN and PF4 evaluated using RT-PCR. The tumor dimensions in the hMSCs group were significantly higher than those of the remaining groups (p < 0.01). The number of metastatic foci in the BMP2+hMSCs group was significantly lower than those of the other groups (p < 0.01). The current results showed that the intraperitoneal route could be efficiently used for targeting hMSCs to the tumoral tissues for effective BMP2 delivery. In this study, the effects of BMP2 transfected hMSCs on human OS and metastasis were promising for achieving osteogenic differentiation and reduced metastatic process.  相似文献   
5.
1. Extracellular enzyme activities were examined in freshwater basins representing a transition from hypertrophy to mesotrophy and in axenic cyanobacterial cultures to evaluate the ecological role of extracellular enzyme activities of cyanobacteria.
2. Aminopeptidase activity was related to the trophic status of the lake basins. The activity was highest in the most eutrophic basin and decreased in the less nutrient-rich basins. Cyanobacteria were the most important autotrophic organisms and aminopeptidase activity was positively associated with cyanobacterial biomass.
3. In an axenic Anabaena batch culture, nitrogenase activity was several orders of magnitude higher than leucine aminopeptidase activity. Nitrate did not have an effect on aminopeptidase activity or growth, but significantly reduced the rate of nitrogen fixation. A high phosphorus concentration at the beginning of the Anabaena batch-culture experiment resulted in reduced phosphatase activity.
4. In Lake Hiidenvesi, aminopeptidase activity probably originated mostly from attached bacteria and less so from cyanobacteria.  相似文献   
6.
The photobiont ultrastructure of the epiphytic lichens Bryoria fuscescens and Bryoria fremontii was studied along the pollution gradient from two Cu-Ni smelters in Nikel and Monchegorsk in northern Finland and north-western Russia. The relationship between ultrastructural characteristics of B. fuscescens and environmental factors (i.e. climate, atmospheric SO2 and bark element concentrations) was studied by using a principal component analysis (PCA) aiming to assess the air quality in a northern environment. Based on PCA, increased plasmolysis and mitochondrial changes in the Trebouxia photobiont were significantly correlated with elevated pollutant concentrations. Degenerated cells, showing altered chloroplasts and electron-translucent pyrenoglobuli, occurred in lichens growing 35–50 km from the Monchegorsk smelter. Cell wall and cytoplasmic lipid volumes, and size of pyrenoglobuli, positively correlated with the distance from the Monchegorsk smelter. Vacuoles and electron-opaque vacuolar deposits were significantly increased at the Finnish site in the vicinity of a pulp mill. Swelling of mitochondrial cristae and thylakoids showed little correlation with environmental factors, but indicated of initial stage of injuries and were observed at several slightly polluted sites in northern Finland and north-western Russia. The results suggest that the severe photobiont injuries of lichens are strongly associated with poor air quality.  相似文献   
7.
1. While both arbuscular mycorrhizal (AM) fungi and plant and insect genotype are well known to influence plant and herbivore growth and performance, information is lacking on how these factors jointly influence the relationship between plants and their natural herbivores. 2. The aim of the present study was to investigate how a natural community of arbuscular mycorrhizal fungi affects the growth of the perennial herb Plantago lanceolata L. (Plantaginaceae), as well as its interaction with the Glanville fritillary butterfly [Melitaea cinxia L. (Nymphalidae)]. For this, a multifactorial experiment was conducted using plant lines originating from multiple plant populations in the Åland Islands, Finland, grown either with or without mycorrhizal fungi. For a subset of plant lines, the impact of mycorrhizal inoculation, plant line, and larval family on the performance of M. cinxia larvae were tested. 3. Arbuscular mycorrhizal inoculation did not have a consistently positive or negative impact on plant growth or herbivore performance. Instead, plant genetic variation mediated the impact of arbuscular mycorrhizal fungi on plant growth, and both plant genetic variation and herbivore genetic variation mediated the response of the herbivore. For both the plant and insect, the impact of the arbuscular mycorrhizal community ranged from mutualistic to antagonistic. Overall, the present findings illustrate that genetic variation in response to mycorrhizal fungi may play a key role in the ecology and evolution of plant–insect interactions.  相似文献   
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10.
Current and future ozone concentrations have the potential to reduce plant growth and increase carbon demand for defence and repair processes, which may result in reduced carbon sink strength of forest trees in long‐term. Still, there is limited understanding regarding the alterations in plant metabolism and variation in ozone tolerance among tree species and genotypes. Therefore, this paper aims to study changes in birch leaf metabolome due to long‐term realistic ozone stress and to relate these shifts in the metabolism with growth responses. Two European white birch (Betula pendula Roth) genotypes showing different ozone sensitivity were growing under 1.4–1.7 × ambient ozone in open‐field conditions in Central Finland. After seven growing seasons, the trees were analysed for changes in leaf metabolite profiling, based on 339 low molecular weight compounds (including phenolics, polar and lipophilic compounds, and pigments) and related whole‐tree growth responses. Genotype caused most of the variance of metabolite concentrations, while ozone concentration was the second principal component explaining the metabolome profiling. The main ozone caused changes included increases in quercetin‐phenolic compounds and compounds related to leaf cuticular wax layer, whereas several compounds related to carbohydrate metabolism and function of chloroplast membranes and pigments (such as chlorophyll‐related phytol derivatives) were decreasing. Some candidate compounds such as surface wax‐related squalene, 1‐dotriacontanol, and dotriacontane, providing growth‐related tolerance against ozone were demonstrated. This study indicated that current growth‐based ozone risk assessment methods are inadequate, because they ignore ecophysiological impacts due to alterations in leaf chemistry.  相似文献   
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