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Pedrotta Tiziana Gobet Erika Schwörer Christoph Beffa Giorgia Butz Christoph Henne Paul D. Morales-Molino César Pasta Salvatore van Leeuwen Jacqueline F. N. Vogel Hendrik Zwimpfer Elias Anselmetti Flavio S. Grosjean Martin Tinner Willy 《Vegetation History and Archaeobotany》2021,30(6):789-813
Vegetation History and Archaeobotany - Knowledge about the vegetation history of Sardinia, the second largest island of the Mediterranean, is scanty. Here, we present a new sedimentary record... 相似文献
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Silvia T. Elias Carolina C. S. Macedo Luiz A. Simeoni Dâmaris Silveira Pérola O. Magalhães Adriana Lofrano-Porto 《Cell cycle (Georgetown, Tex.)》2016,15(7):948-956
Plant-derived molecules showing antineoplastic effects have recently gained increased attention as potential adjuvants to traditional therapies for various cancers. Cerrado biome in Brazil contains high floral biodiversity, but knowledge about the potential therapeutic effects of compounds derived from that flora is still limited. The present study investigated the antineoplastic activity of Erythroxylum daphnites Mart., a Brazilian native plant from Cerrado biome, in the SCC-9 oral squamous cell carcinoma cell line. Cells were treated with various concentrations of hexane extract of Erythroxylum daphnites leaves (EDH) and assessed for cytotoxicity, proliferation, and apoptosis. Thin layer chromatography was conducted to characterize the substances present in EDH. Our results showed that EDH exerted anti-proliferative effects in SCC-9 cells by stabilizing the cell cycle at G1 phase in association with reduced intracellular levels of cyclins D and E and increased level of p21. EDH also demonstrated pro-apoptotic properties, as shown by an increased expression of caspase-3. Triterpenes were the major constituents of EDH. Our findings demonstrated a cytotoxic effect of EDH against SCC-9 cells in vitro mediated by the restraint of cellular proliferation and induction of apoptosis. Taken together, these findings support EDH constituents as potential therapeutic adjuvants for oral cancer. 相似文献
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Estimates of population size are critical for conservation and management, but accurate estimates are difficult to obtain for many species. Noninvasive genetic methods are increasingly used to estimate population size, particularly in elusive species such as large carnivores, which are difficult to count by most other methods. In most such studies, genotypes are treated simply as unique individual identifiers. Here, we develop a new estimator of population size based on pedigree reconstruction. The estimator accounts for individuals that were directly sampled, individuals that were not sampled but whose genotype could be inferred by pedigree reconstruction, and individuals that were not detected by either of these methods. Monte Carlo simulations show that the population estimate is unbiased and precise if sampling is of sufficient intensity and duration. Simulations also identified sampling conditions that can cause the method to overestimate or underestimate true population size; we present and discuss methods to correct these potential biases. The method detected 2–21% more individuals than were directly sampled across a broad range of simulated sampling schemes. Genotypes are more than unique identifiers, and the information about relationships in a set of genotypes can improve estimates of population size. 相似文献
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Mnica Arias Marianne Elias Christine Andraud Serge Berthier Doris Gomez 《Journal of evolutionary biology》2020,33(2):247-252
Predation is a ubiquitous and strong selective pressure on living organisms. Transparency is a predation defence widespread in water but rare on land. Some Lepidoptera display transparent patches combined with already cryptic opaque patches. A recent study showed that transparency reduced detectability of aposematic prey with conspicuous patches. However, whether transparency has any effect at reducing detectability of already cryptic prey is still unknown. We conducted field predation experiments with free avian predators where we monitored and compared survival of a fully opaque grey artificial form (cryptic), a form including transparent windows and a wingless artificial butterfly body. Survival of the transparent forms was similar to that of wingless bodies and higher than that of fully opaque forms, suggesting a reduction of detectability conferred by transparency. This is the first evidence that transparency decreases detectability in cryptic terrestrial prey. Future studies should explore the organization of transparent and opaque patches in animals and their interplay on survival, as well as the costs and other potential benefits associated with transparency on land. 相似文献
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Elias Katz 《Arts Education Policy Review》2013,114(4):2-44
Abstract A well-dressed art viewer (who appears to be affluent and highly educated) is observed gazing at several contemporary works in an art museum gallery. Out of this gentleman's view, in an adjacent gallery, a blue-collar worker enters carrying a new and attractive, but ordinary-looking door that he quickly but carefully places on the floor, leaning it against a wall near several artworks. The worker exits the gallery just as the art viewer enters it. With great concentration, the viewer contemplates all of the artworks he sees. His attention is immediately drawn to the door left behind by the workman. The viewer is intrigued by the door, which he obviously mistakes for a work of art. The door is studied intensively and at length by the viewer who seems to be searching for layers of meaning. That deep intellectual pursuit is interrupted abruptly, however, when the worker reenters the gallery, picks up the door, and carries it away. Evidently, the worker's job is to install the door elsewhere in the museum, no doubt where it will not be mistaken for a work of art. Had he been asked to comment on the art viewer's encounter with the door, the worker would surely have expressed some degree of puzzlement and criticism because—from the worker's viewpoint—anyone with even a small measure of common sense (something the “expert” art viewer apparently lacks) knows the difference between a door and a work of art, no matter how finely crafted the door may be. 相似文献
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Ragnar Österberg Per Elias Jörgen Kjems Rogert Bauer 《Journal of biomolecular structure & dynamics》2013,31(6):1111-1120
Abstract The complex formation between elongation factor Tu (EF-Tu), GTP, and valyl-tRNAVal 1A has been investigated in a hepes buffer of “pH” 7.4 and 0.2 M ionic strength using the small-angle neutron scattering method at concentrations of D2O where EF-Tu (42% D2O) and tRNA (71% D2O) are successively matched by the solvents. The results indicate that EF-Tu undergoes a conformational change and contracts as a result of the complex formation, since the radius of gyration decreases by 15% from 2.82 to 2.39 nm. tRNAVal 1A, on the other hand, seems to mainly retain its conformation within the complex, since the radii of gyration for the free (after correction for interparticular scattering) and complexed form are essentially the same. 2.38 and 2.47 nm, respectively. 相似文献