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1.

The Eragrostis pilosa complex (Poaceae) comprises five widely distributed and regionally invasive species—E. albensis, E. amurensis, E. imberbis, E. multicaulis, and E. pilosa, distinguished by tiny and variable morphological characters and with so far unknown phylogenetic relationships. Recently, some doubts have been raised about the status of an invasive glandular morphotype occurring in Central Europe assigned either to E. amurensis or to E. albensis. Here, we addressed this issue by analysing morphology, internal transcribed spacers of nuclear ribosomal DNA, and five inter-simple sequence repeat markers. The genetic evidence supported closer relationship of this glandular morphotype to eglandular E. albensis, widely established in Central Europe, than to glandular E. amurensis described from Asia. We propose to adopt a new taxonomic treatment that E. albensis includes both eglandular and glandular individuals, and to classify the glandular ones as E. albensis var. scholziana M. Nobis & A. Wróbel var. nova. Currently this new taxon is known from a dozen of localities in Central Europe and is invasive in the lower section of the Oder River valley, whereas Eragrostis albensis var. albensis has already spread widely across Europe in riparian phytocenoses and anthropogenic habitats. Since probably the first registered records in 1940s, it has been observed in European part of Russia, Belarus, Ukraine, Poland, Slovakia, Czech Republic, Germany, Austria, the Netherlands, and its further invasion is likely to proceed. We provided distribution maps concerning spread dynamics of E. albensis in Europe from 1947 to 2020. In total, the species has been observed on over 1300 localities so far, most of which were found after 2000.

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2.
A. Nowak  S. Nowak  M. Nobis  A. Nobis 《Plant biosystems》2013,147(6):1199-1210
The paper presents the results of phytosociological research conducted on the vegetation of rock habitats in the montane and colline zones of the Pamir-Alai Mountains (Tajikistan). During field surveys done in 2010–2013, 122 phytosociological relevés were sampled. Plant species were recorded according to the Braun-Blanquet cover-abundance scale. The vegetation studies were carried out generally in the western Pamir-Alai and south-western Tian Shan Mts, especially in the Zeravshan, Hissar, Hazratishoh, Darvaz, Rushan, Turkestan, Kuramin and Vanch ranges. A synopsis of the rock communities of the montane and colline zones in Tajikistan is proposed. The collected material presents most of the variability among the plant communities of rock crevices and fissures on calcareous as well as acidic substrates in the montane and colline zones in Tajikistan. As a result of field research and numerical analyses, eight associations have been distinguished: Scutellarietum hissaricae, Scutellarietumschugnanicae, Scutellarietum zaprjagaevii, Scutellarietum baldshuanicae, Tylospermetumlignosae, Dionysietum involucratae A. Nowak, M. Nobis, S. Nowak & A. Nobis, 2014, Nanorrhinetum ramosissimi, Campanuletum albertii and the community of Scutellaria adenostegia within new alliance – Caricion koshevnikovii. The main factors determining the species composition of classified associations seem to be the geography of the distribution range, elevation above sea level, rock type and exposition.  相似文献   
3.
Cambridge mathematician and philosopher W. K. Clifford (1879/1999) con-cluded his famous essay, "The Ethics of Belief" with the bold claim that "it is wrong always, everywhere, and for anyone to believe anything upon insufficient evidence" (p.77). Clifford's enthusiasm for evidentialism-the principle that one should proportion one's belief to the strength of the evidence-may have been overzealous, but a plausible interpretation of his view is this: Because beliefs of-ten have serious moral consequences, one should base one's beliefs on the evi-dence, and it is intellectually and morally irresponsible not to do so. This per-spective motivates recent so-called "evidence-based" methods in the fields of medicine and education. Balcombe's (2000, 2001) case for replacing learning methods that require pain, suffering, and death for animals with methods that do not (computer-assisted learning, three-dimensional models, videotapes, and other alternatives) can be seen as motivated by this evidentialist perspective. Balcombe provided a wealth of empirical evidence from educational studies to show that in most contexts animal dissection is not necessary-and even counterproductive-to achieve valid educa-tional goals, especially higher order goals (concept learning and problem solving). He demonstrated that no sound defense of dissection has been given. Can we learn as effectively without hurting or killing another being? If so, why do we not try? Many of the studies Balcombe cites have supported sufficiently the adequacy and, often, superiority of learning methods that do not harm animals or students. The first of the aforementioned questions is being answered; we can learn effectively with these non-detrimental methods. Those who seek to educate (and accept the prin-ciple of "do no harm") must seize the second question because they see, in the big pic-ture, the benefit for themselves, their students, their society, and other sentient beings. (p. 132)  相似文献   
4.
Cell migration is fundamental to many aspects of biology, including development, wound healing, the cellular responses of the immune system, and metastasis of tumor cells. Migration has been studied on glass coverslips in order to make cellular dynamics amenable to investigation by light microscopy. However, it has become clear that many aspects of cell migration depend on features of the local environment including its elasticity, protein composition, and pore size, which are not faithfully represented by rigid two dimensional substrates such as glass and plastic. Furthermore, interaction with other cell types, including stromal fibroblasts and immune cells, has been shown to play a critical role in promoting the invasion of cancer cells. Investigation at the molecular level has increasingly shown that molecular dynamics, including response to drug treatment, of identical cells are significantly different when compared in vitro and in vivo. Ideally, it would be best to study cell migration in its naturally occurring context in living organisms, however this is not always possible. Intermediate tissue culture systems, such as cell derived matrix, matrigel, organotypic culture (described here) tissue explants, organoids, and xenografts, are therefore important experimental intermediates. These systems approximate certain aspects of an in vivo environment but are more amenable to experimental manipulation such as use of stably transfected cell lines, drug treatment regimes, long term and high-resolution imaging. Such intermediate systems are especially useful as proving grounds to validate probes and establish parameters required to image the dynamic response of cells and fluorescent reporters prior to undertaking imaging in vivo. As such, they can serve an important role in reducing the need for experiments on living animals.  相似文献   
5.
The NRAMP 1 gene is a major candidate gene influencing the outcome of infections with intracellular pathogens in numerous species. NRAMP 1 is highly conserved in many mammalian species and the NRAMP 1 gene shows considerable conservation in structure between mice and humans. The association of NRAMP 1 gene polymorphisms with disease in cattle has been limited to a single microsatellite located within the 3'-non coding region of the bovine NRAMP 1 gene. In order to facilitate further studies on this important gene, we now report the nearly complete structure of the bovine NRAMP 1 gene, including sizes and positions of 13 introns relative to the bovine NRAMP 1 gene coding sequence and the DNA sequence of intron-exon junctions. Comparison of the bovine, murine and human NRAMP 1 gene structures revealed a high degree of conservation in intron placement, though the lengths of several introns were less-well conserved. In general, the greatest divergence in intron lengths occurred in regions of the NRAMP 1 gene displaying the lowest coding sequence conservation. In addition, mutations near intron-exon junctions could account for 25 of the 75 total amino acid differences between murine and bovine NRAMP 1. Using information gained through this study, it was possible to rapidly identify a novel polymorphism within the bovine NRAMP 1 gene intron X. This polymorphism was shown by direct DNA sequence analysis to consist of insertion of three guanine nucleotides at positions 37,40 and 98 relative to the intron X start point. Initial scans of several cattle breeds suggest that the two intron X alleles identified here are stable and widespread in the Bos taurus population.  相似文献   
6.
Anorexia nervosa is an eating disorder often associated with intestinal disorders. To explore the underlying mechanisms of these disorders, the colonic proteome was evaluated during activity‐based anorexia. Female C57Bl/6 mice were randomized into three groups: Control, Limited Food Access (LFA) and Activity‐Based Anorexia (ABA). LFA and ABA mice had a progressive limited access to food but only ABA mice had access to an activity wheel. On colonic mucosal protein extracts, a 2D PAGE‐based comparative proteomic analysis was then performed and differentially expressed proteins were identified by LC‐ESI‐MS/MS. Twenty‐seven nonredundant proteins that were differentially expressed between Control, LFA, and ABA groups were identified. ABA mice exhibited alteration of several mitochondrial proteins involved in energy metabolism such as dihydrolipoyl dehydrogenase and 3‐mercaptopyruvate sulfurtransferase. In addition, a downregulation of mammalian target of rapamycin (mTOR) pathway was observed leading, on the one hand, to the inhibition of protein synthesis, evaluated by puromycin incorporation and mediated by the increased phosphorylation of eukaryotic elongation factor 2, and on the other hand, to the activation of autophagy, assessed by the increase of the marker of autophagy, form LC3‐phosphatidylethanolamine conjugate/Cytosolic form of Microtubule‐associated protein 1A/1B light chain 3 (LC3II/LC3I) ratio. Colonic mucosal proteome is altered during ABA suggesting a downregulation of energy metabolism. A decrease of protein synthesis and an activation of autophagy were also observed mediated by mTOR pathway.  相似文献   
7.
Aim To analyse the effects of simultaneously using spatial and phylogenetic information in removing spatial autocorrelation of residuals within a multiple regression framework of trait analysis. Location Switzerland, Europe. Methods We used an eigenvector filtering approach to analyse the relationship between spatial distribution of a trait (flowering phenology) and environmental covariates in a multiple regression framework. Eigenvector filters were calculated from ordinations of distance matrices. Distance matrices were either based on pure spatial information, pure phylogenetic information or spatially structured phylogenetic information. In the multiple regression, those filters were selected which best reduced Moran's I coefficient of residual autocorrelation. These were added as covariates to a regression model of environmental variables explaining trait distribution. Results The simultaneous provision of spatial and phylogenetic information was effectively able to remove residual autocorrelation in the analysis. Adding phylogenetic information was superior to adding purely spatial information. Applying filters showed altered results, i.e. different environmental predictors were seen to be significant. Nevertheless, mean annual temperature and calcareous substrate remained the most important predictors to explain the onset of flowering in Switzerland; namely, the warmer the temperature and the more calcareous the substrate, the earlier the onset of flowering. A sequential approach, i.e. first removing the phylogenetic signal from traits and then applying a spatial analysis, did not provide more information or yield less autocorrelation than simple or purely spatial models. Main conclusions The combination of spatial and spatio‐phylogenetic information is recommended in the analysis of trait distribution data in a multiple regression framework. This approach is an efficient means for reducing residual autocorrelation and for testing the robustness of results, including the indication of incomplete parameterizations, and can facilitate ecological interpretation.  相似文献   
8.
Molecular Biology Reports - Stipa pennata (Poaceae), has become a rare and endangered species in Central Europe due habitat loss and fragmentation. This species is characterized by high...  相似文献   
9.
Ecological research has been repeatedly criticized for its general lack of progress. While it has proved difficult to reveal scientific progress, from a subjective view trends in ecology seems evident. In order to objectively detect principal trends in this broad discipline during the past 25 years (1978–2002), we performed several word and co-word analyses on titles and abstracts of articles that appeared in five core journals of ecology: «Ecology>>, «Oecologia>>, «Oikos>>, «Journal of Animal Ecology>> and «Journal of Ecology>>. A general time gradient in the use of words was evident and words with a positive trend dominated. Trend words derived from article titles were used to perform co-word analyses on abstracts available since 1991. Besides a trend towards the study of processes most important ecological fields found are landscape ecology, biodiversity, ecosystem research, modelling, and food-web/predator–prey interactions. A semantic map of trend words was built by ordination. In the map, words formed a continuous space with the three thematic directions «biotic>>, «abiotic>> and «temporal & spatial>> representing the classic aspects of ecological research. With respect to the obvious trends and features derived from our analyses, we suggest that the results represent real scientific progress in ecology as a pluralistic, multi-aspect and multiple-causation discipline. Such a progress could hardly be observed from details in sub-disciplines.  相似文献   
10.
Messenger RNA synthesis in synchronized Chinese hamster ovary cells   总被引:1,自引:0,他引:1  
Chinese hamster ovary cells were synchronized without inhibitors by mitotic selection and labelled in G1, S or G2 phase by incubation for 90 min with [3H]- OR [14C]uridine. Purified polyribosomes were extracted with phenol and the polyadenylated mRNA prepared by poly(U)-Sepharose chromatography. Poly-adenylated [3H]uridine-labelled mRNA from the G1 phase of the cell cycle was compared by exponential polyacrylamide gel electrophoresis in formamide with [14C] uridine-labelled polyadenylated nRNA from the S or G2 phase. The electrophoretic patterns obtained correspond to the size range expected for mRNA (7-28 S). No prominent differences were detected between mRNAs synthesized in different phases of the cell cycle. From these data we conclude that the major size classes of polyribosomal poly(A)-containing mRNA are synthesized in equal ratios throughout the cell cycle.  相似文献   
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