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971.
Prediction of allergic pollen concentration is one of the most important goals of aerobiology. Past studies have used a broad range of modeling techniques; however, the results cannot be directly compared owing to the use of different datasets, validation methods, and evaluation metrics. The main aim of this study was to compare nine statistical modeling techniques using the same dataset. An additional goal was to assess the importance of predictors for the best model. Aerobiological data for Corylus, Alnus, and Betula pollen counts were obtained from nine cities in Poland and covered between five and 16 years of measurements. Meteorological data from the AGRI4CAST project were used as a predictor variables. The results of 243 final models (3 taxa \(\times\)  9 cities \(\times\) 9 techniques) were validated using a repeated k-fold cross-validation and compared using relative and absolute performance statistics. Afterward, the variable importance of predictors in the best models was calculated and compared. Simple models performed poorly. On the other hand, regression trees and rule-based models proved to be the most accurate for all of the taxa. Cumulative growing degree days proved to be the single most important predictor variable in the random forest models of Corylus, Alnus, and Betula. Finally, the study suggested potential improvements in aerobiological modeling, such as the application of robust cross-validation techniques and the use of gridded variables.  相似文献   
972.
Paper presents the phenomenon of thanatosis or death-feigning in selected aphids species. This specific reaction was predominantly analysed on the example of aphid subfamily Lachninae. Individuals of this group were used in experiments, during which a thanatotic response was induced with various results. The response differed from prolonged thanatosis, lasting for several minutes (Eulachnus rileyi), through shrinking behaviour (e. g. in Stomaphis graffii) to non-responsive species such as Cinara (Schizolachnus) pineti. The large interspecies variation of observed responses can be linked to other defensive mechanisms existing in the studied species, as well as to their mutualistic relationship with ants. The behaviour of shrinking is hypothesized to be the mutualistic response, developed from thanatosis, and being adapted to transportation by ant workers.  相似文献   
973.
Cardiovascular diseases are a major cause of human death worldwide. Excessive proliferation of vascular smooth muscle cells contributes to the etiology of such diseases, including atherosclerosis, restenosis, and pulmonary hypertension. The control of vascular cell proliferation is complex and encompasses interactions of many regulatory molecules and signaling pathways. Herein, we recapitulated the importance of signaling cascades relevant for the regulation of vascular cell proliferation. Detailed understanding of the mechanism underlying this process is essential for the identification of new lead compounds (e.g., natural products) for vascular therapies.  相似文献   
974.
The objective of this study was to develop a multiplex detection and identification protocol for bacterial soft rot coliforms, namely Pectobacterium wasabiae (Pw), Pectobacterium atrosepticum (Pba) and Dickeya spp., responsible for potato blackleg and tuber soft rot. The procedures were derived from the phylogenetic relationships of these and other Enterobacteriaceae based on recA sequences. The group of Pw strains was highly homogeneous and could be distinguished from the other species. A ligation‐based method for detection of Pw was developed. Five padlock probes (PLPs) were designed, targeting recA sequences to identify the Pw, Pba or Dickeya spp., whereas a sixth probe recognised recA sequences of all soft rot coliforms including Pectobacterium carotovorum subsp. carotovorum (Pcc). Two PLP‐based applications were developed: one using real‐time PCR and one using universal microarrays. Assay sensitivity and specificity were demonstrated using 71 strains of Pw, Pcc, Pba and Dickeya spp. Both multiplex methods can be potentially used for seed testing and in ecological studies, but further validation is required.  相似文献   
975.
976.
Single macropterous female of Trigonocranus emmeae Fieber, 1876 has been found during the faunistic studies in semi-natural plant communities of Oświęcim city in southern Poland. It is the first record of this species in Poland. Trigonocranus emmeae is rarely collected within the wide range of its distribution, mostly due to its hidden life mode.  相似文献   
977.
A case of late onset GM2 gangliosidodis with spinal muscular atrophy phenotype followed by cerebellar and extrapyramidal symptoms is presented. Genetic analysis revealed compound heterozygous mutation in exon 10 of the HEXA gene. Patient has normal intelligence and emotional reactivity. Neuroimaging tests of the brain showed only cerebellar atrophy consistent with MR spectroscopy (MRS) abnormalities. (18)F-fluorodeoxyglucose positron emission tomography (18)F-FDG PET/CT of the brain revealed glucose hypometabolism in cerebellum and in temporal and occipital lobes bilaterally.  相似文献   
978.
1-[(4-Methylphenyl)oxy]pyrrolidine-2,5-dione and 1-[(4-methylphenyl)oxy]piperidine-2,6-dione react in a Lossen-type reaction with primary alcohols in the presence of triethylamine to furnish corresponding N α-urethane-protected β-alanine and γ-aminopropionic acid (GABA), respectively, with excellent yields and purities, in an essentially “one-pot” procedure.  相似文献   
979.
Blooms of cyanobacteria producing very toxic secondary metabolites (especially microcystins) are potent environmental stressors, hazardous not only to aquatic animals but also to public health. The purpose of this study was to investigate the effects of an extract containing microcystins on immune cells isolated from the common carp (Cyprinus carpio L.). In the present study it has been found that the extract induced apoptosis and inhibited in vitro lymphocyte proliferation. In addition, the results indicated the possible role of oxidative stress in this cytotoxicity and apoptosis. The in vivo investigations showed that the extract containing microcystins had greater suppressive effects on the essential functions of immune cells (intracellular reactive oxygen species production and lymphocyte proliferation) than the pure toxin alone. Moreover, immersion of fish in the toxic extract caused changes in the mRNA levels of various pro- and anti-inflammatory cytokines in carp leukocytes, while after exposure to the pure toxin, only IL1-β expression was markedly up-regulated. The observed modulatory effects on immune cells could have important implications for the health of planktivorous fish, which feed more frequently on toxic cyanobacteria.  相似文献   
980.
The T > C single nucleotide polymorphism (SNP) in the MIR2467 gene was investigated in order to confirm its presence in cattle genome and to check for possible differences in its genotype distribution among different breeds. Additional purpose of the study was to investigate in silico potential effect of that substitution on the structure and stability of precursor mir-2467. The study involved 634 individuals of five cattle breeds: Angus, Hereford, Holstein-Friesian, Jersey, and Limousin, which were genotyped using PCR-RFLP assay. In this study, the presence of T > C polymorphism at position 24 was observed in all the cattle breeds excepting Hereford. In addition, the differences in the genotype distribution among analyzed breeds were indicated. On the basis of minimum free energy structure prediction, the C allele was indicated to have possible impact on decreasing the stability of the pre-mir-2467, thus altering its ability to regulate target genes expression.  相似文献   
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