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881.
Arkadiusz Sołtysiak 《HOMO》2012,63(2):110-113
Dental caries is an infectious disease caused by oral acidophilic bacteria feeding on fermentable sugars, e.g. Streptococcus mutans. The frequency of dental caries in Neandertals was very low. This was usually explained as the result of a low-sugar diet. Recent research, however, revealed some regional differences between European and Near Eastern Neandertals, with the latter consuming considerable amounts of plants including highly cariogenic dates. This discovery, compared with the results of research on genetic diversity of S. mutans, may suggest that this species, and perhaps other most virulent species, were absent in the oral flora of Neandertals. 相似文献
882.
Puc M 《International journal of biometeorology》2012,56(2):395-401
Birch pollen is one of the main causes of allergy during spring and early summer in northern and central Europe. The aim of
this study was to create a forecast model that can accurately predict daily average concentrations of Betula sp. pollen grains in the atmosphere of Szczecin, Poland. In order to achieve this, a novel data analysis technique—artificial
neural networks (ANN)—was used. Sampling was carried out using a volumetric spore trap of the Hirst design in Szczecin during
2003–2009. Spearman’s rank correlation analysis revealed that humidity had a strong negative correlation with Betula pollen concentrations. Significant positive correlations were observed for maximum temperature, average temperature, minimum
temperature and precipitation. The ANN resulted in multilayer perceptrons 366 8: 2928-7-1:1, time series prediction was of
quite high accuracy (SD Ratio between 0.3 and 0.5, R > 0.85). Direct comparison of the observed and calculated values confirmed good performance of the model and its ability
to recreate most of the variation. 相似文献
883.
Myśliwa-Kurdziel B Jemioła-Rzemińska M Turek E Strzałka K Malec P 《Acta biochimica Polonica》2012,59(1):57-60
Protochlorophyllide (Pchlide) accumulation and xantophyll composition were studied in 5-day old etiolated seedlings of three ecotypes of Arabidopsis thaliana: Columbia (Col-0), Landsberg erecta (Ler) and Wassiliewska (Ws). The total Pchlide level as measured by fluorescence spectroscopy varied significantly between ecotypes. A rapid HPLC method revealed quantitative differences in carotenoid composition. It was found that in the Ler ecotype any enhanced accumulation of Pchlide correlates with an increased level of lutein, suggesting the role of enzymes involved in lutein synthesis in cross-regulation between chlorophyll and carotenoid biosynthetic pathways. The function of the dark-accumulated carotenoid pool in seedling de-etiolation is discussed. 相似文献
884.
EPR spectroscopy using 5-doxylstearic acid (5-SASL) and 16-doxylstearic acid (16-SASL) spin probes was used to study the fluidity of thylakoid membranes. These were isolated from wild type Synechocystis and from several mutants in genes encoding selected enzymes of the carotenoid biosynthesis pathway and/or acyl-lipid desaturases. Cyanobacteria were cultivated at 25°C and 35°C under different light regimes: photoautotrophically (PAG) and/or in light-activated heterotrophic conditions (LAHG). The relative fluidity of membranes was estimated from EPR spectra based on the empirical outermost splitting parameter in a temperature range from 15°C to 40°C. Our findings demonstrate that in native thylakoid membranes the elimination of xanthophylls decreased fluidity in the inner membrane region under optimal growth conditions (25°C) and increased it under sublethal heat stress (35°C). This indicated that the overall fluidity of native photosynthetic membranes in cyanobacteria may be influenced by the ratio of polar to non-polar carotenoid pools under different environmental conditions. 相似文献
885.
The Ortolan bunting Emberiza hortulana was censused in Poland during the Common Breeding Birds Monitoring Project in 2003–2009. Data from 683 monitoring polygons,
covering in total more than 0.23% of the country, were used in the analysis. Based on the data and environmental information
gathered in GIS databases (Corine land cover “CLC2000 and 2006” database, digital elevation model “GTOPO30” dataset, “Wordclim”
dataset, and NDVI dataset), we modeled a habitat- and spatial-related variation of the Ortolan bunting’s presence. Birds were
recorded in 13.2% grid cells. The mean density was 0.5 individual/km2. We modeled the spatial presence of birds using multivariate adaptive regression splines (MARS). Then models were cross-validated
to check their consistency. The environment-use model shows that the Ortolan bunting prefers extensively cultivated farmland
dominated by non-irrigated arable fields, small coniferous and mixed forests, complex cultivation patterns, and meadows. The
preferred areas are located on lowlands in western and central parts of the country where the climate is the driest and warmest.
Such a repeatable spatial pattern model of the population helped to create a predictive map of the Ortolan bunting’s presence
in Poland. The general rule is that the probability gradient of its presence increases from the northeastern part of the country
to the central and southwestern parts of Poland. Additionally, the Ortolan bunting avoids severe continental climate and regions
with dense ground-level vegetation. 相似文献
886.
887.
Katarzyna Trzmiel Małgorzata Jeżewska Aleksandra Zarzyńska 《Journal of Phytopathology》2012,160(10):614-616
The virus in naturally infected, stunted triticale plants was identified as soil‐borne wheat mosaic virus (SBWMV). The infected plants were collected in the Southern Wielkopolska region (Western Poland). Molecular analysis including RT‐PCR, and sequencing of the complete coding sequence of coat protein gene, was performed. The sequence of the Polish isolate of SBWMV (SBWMV‐Pol1) shared 100, 99 and 98% identities with the corresponding regions of De1 (AF519799), OKL‐1 (X81639) and US‐Nebraska (L07938) isolates of SBWMV, respectively. Phylogenetic analyses showed that the Polish isolate, SBWMV‐Pol1, clustered together with other SBWMV isolates. This is the first report of the occurrence of SBWMV in Poland and the second of its presence in Europe. 相似文献
888.
Trocha LK Kałucka I Stasińska M Nowak W Dabert M Leski T Rudawska M Oleksyn J 《Mycorrhiza》2012,22(2):121-134
Non-native tree species have been widely planted or have become naturalized in most forested landscapes. It is not clear if
native trees species collectively differ in ectomycorrhizal fungal (EMF) diversity and communities from that of non-native
tree species. Alternatively, EMF species community similarity may be more determined by host plant phylogeny than by whether
the plant is native or non-native. We examined these unknowns by comparing two genera, native and non-native Quercus robur and Quercus rubra and native and non-native Pinus sylvestris and Pinus nigra in a 35-year-old common garden in Poland. Using molecular and morphological approaches, we identified EMF species from ectomycorrhizal
root tips and sporocarps collected in the monoculture tree plots. A total of 69 EMF species were found, with 38 species collected
only as sporocarps, 18 only as ectomycorrhizas, and 13 both as ectomycorrhizas and sporocarps. The EMF species observed were
all native and commonly associated with a Holarctic range in distribution. We found that native Q. robur had ca. 120% higher total EMF species richness than the non-native Q. rubra, while native P. sylvestris had ca. 25% lower total EMF species richness than non-native P. nigra. Thus, across genera, there was no evidence that native species have higher EMF species diversity than exotic species. In
addition, we found a higher similarity in EMF communities between the two Pinus species than between the two Quercus species. These results support the naturalization of non-native trees by means of mutualistic associations with cosmopolitan
and novel fungi. 相似文献
889.
Cantin LD Bayrakdarian M Buon C Grazzini E Hu YJ Labrecque J Leung C Luo X Martino G Paré M Payza K Popovic N Projean D Santhakumar V Walpole C Yu XH Tomaszewski MJ 《Bioorganic & medicinal chemistry letters》2012,22(7):2565-2571
Purinergic receptor P2X3 has been linked to analgesia in a number of pre-clinical models of pain, and is expressed in the human pain perception pathway. Only few P2X3-selective antagonists have been reported to date. This Letter describes the SAR and in vivo analgesic profile of a novel scaffold of selective P2X3 antagonists. 相似文献
890.