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951.
Longer wings for faster springs – wing length relates to spring phenology in a long‐distance migrant across its range
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Steffen Hahn Fränzi Korner‐Nievergelt Tamara Emmenegger Valentin Amrhein Tibor Csörgő Arzu Gursoy Mihaela Ilieva Pavel Kverek Javier Pérez‐Tris Simone Pirrello Pavel Zehtindjiev Volker Salewski 《Ecology and evolution》2016,6(1):68-77
In migratory birds, morphological adaptations for efficient migratory flight often oppose morphological adaptations for efficient behavior during resident periods. This includes adaptations in wing shape for either flying long distances or foraging in the vegetation and in climate‐driven variation of body size. In addition, the timing of migratory flights and particularly the timely arrival at local breeding sites is crucial because fitness prospects depend on site‐specific phenology. Thus, adaptations for efficient long‐distance flights might be also related to conditions at destination areas. For an obligatory long‐distance migrant, the common nightingale, we verified that wing length as the aerodynamically important trait, but not structural body size increased from the western to the eastern parts of the species range. In contrast with expectation from aerodynamic theory, however, wing length did not increase with increasing migration distances. Instead, wing length was associated with the phenology at breeding destinations, namely the speed of local spring green‐up. We argue that longer wings are beneficial for adjusting migration speed to local conditions for birds breeding in habitats with fast spring green‐up and thus short optimal arrival periods. We suggest that the speed of spring green‐up at breeding sites is a fundamental variable determining the timing of migration that fine tune phenotypes in migrants across their range. 相似文献
952.
953.
Tamara Provencher Frédéric Olivier Réjean Tremblay Céline Audet 《Environmental Biology of Fishes》2018,101(10):1483-1492
Winter flounder (Pseudopleuronectes americanus) is a benthic flatfish that is economically important for recreational and commercial fishing in North America. In the last twenty years, the species has undergone a drastic decline, mainly due to anthropic influence. The goal of this study was to gain knowledge on habitat preferences and behavior of juvenile winter flounder to improve the management of natural stocks and optimize release sites of juveniles produced for stock enhancement. Three abiotic factors (sediment, current, and salinity) potentially influencing the distribution of flatfish species were tested in a recircurlating flume with juvenile winter flounder. Time budgets of observed behaviors including swimming, orientation, and burying capacity were analyzed. Sediment texture was the only factor that significantly influenced the burying behavior of winter flounder juveniles; shear velocity, salinity, and sediment had no effect on the orientation of juveniles. 相似文献
954.
955.
Vladimir N. Podust Tamara O. Korobeinicheva George A. Nevinsky Asja S. Levina Olga I. Lavrik 《Molecular biology reports》1990,14(4):247-249
Template-primer dependent inactivation of human DNA polymerase and Klenow fragment of E. coli DNA polymerase I by adenosine 2,3-riboepoxide 5-triphosphate was used for quantitative analysis of the Kd values for oligonucleotide primers of different length. The Kd values are smaller by a factor of 2.5 than the Km values for the same primers determined in the reaction of DNA polymerization in the case of DNA polymerase . The Kd and Km values are nearly the same for Klenow fragment. Such approach to the determination of Km/Kd ratio can likely be used for detailed quantitative analysis of DNA polymerases.Abbreviations epATP
adenosine 2,3-riboepoxide 5-triphosphate
- KF
Klenow fragment of E. coli DNA polymerase I
- Pol I
E. coli DNA polymerase I
- Pol
human placenta DNA polymerase 相似文献
956.
Daniel Lysák Monika Holubová Tamara Bergerová Monika Vávrová Giuseppina Cristina Cangemi Rachele Ciccocioppo Peter Kruzliak Pavel Jindra 《Cell and tissue banking》2016,17(1):1-9
Cell therapy products represent a new trend of treatment in the field of immunotherapy and regenerative medicine. Their biological nature and multistep preparation procedure require the application of complex release criteria and quality control. Microbial contamination of cell therapy products is a potential source of morbidity in recipients. The automated blood culture systems are widely used for the detection of microorganisms in cell therapy products. However the standard 2-week cultivation period is too long for some cell-based treatments and alternative methods have to be devised. We tried to verify whether a shortened cultivation of the supernatant from the mesenchymal stem cell (MSC) culture obtained 2 days before the cell harvest could sufficiently detect microbial growth and allow the release of MSC for clinical application. We compared the standard Ph. Eur. cultivation method and the automated blood culture system BACTEC (Becton Dickinson). The time to detection (TTD) and the detection limit were analyzed for three bacterial and two fungal strains. The Staphylococcus aureus and Pseudomonas aeruginosa were recognized within 24 h with both methods (detection limit ~10 CFU). The time required for the detection of Bacillus subtilis was shorter with the automated method (TTD 10.3 vs. 60 h for 10–100 CFU). The BACTEC system reached significantly shorter times to the detection of Candida albicans and Aspergillus brasiliensis growth compared to the classical method (15.5 vs. 48 and 31.5 vs. 48 h, respectively; 10–100 CFU). The positivity was demonstrated within 48 h in all bottles, regardless of the size of the inoculum. This study validated the automated cultivation system as a method able to detect all tested microorganisms within a 48-h period with a detection limit of ~10 CFU. Only in case of B. subtilis, the lowest inoculum (~10 CFU) was not recognized. The 2-day cultivation technique is then capable of confirming the microbiological safety of MSC and allows their timely release for clinical application. 相似文献
957.
What it takes to invade grassland ecosystems: traits,introduction history and filtering processes
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Marta Carboni Tamara Münkemüller Sébastien Lavergne Philippe Choler Benjamin Borgy Cyrille Violle Franz Essl Cristina Roquet François Munoz DivGrass Consortium Wilfried Thuiller 《Ecology letters》2016,19(3):219-229
Whether the success of alien species can be explained by their functional or phylogenetic characteristics remains unresolved because of data limitations, scale issues and weak quantifications of success. Using permanent grasslands across France (50 000 vegetation plots, 2000 species, 130 aliens) and building on the Rabinowitz's classification to quantify spread, we showed that phylogenetic and functional similarities to natives were the most important correlates of invasion success compared to intrinsic functional characteristics and introduction history. Results contrasted between spatial scales and components of invasion success. Widespread and common aliens were similar to co‐occurring natives at coarse scales (indicating environmental filtering), but dissimilar at finer scales (indicating local competition). In contrast, regionally widespread but locally rare aliens showed patterns of competitive exclusion already at coarse scale. Quantifying trait differences between aliens and natives and distinguishing the components of invasion success improved our ability to understand and potentially predict alien spread at multiple scales. 相似文献
958.
Michael Tayao Juliana Andrici Mahtab Farzin Adele Clarkson Loretta Sioson Nicole Watson Terence C Chua Tamara Sztynda Jaswinder S Samra Anthony J Gill 《PloS one》2016,11(3)
Background
Pancreatic cancer is both common and highly lethal and therefore new biomarkers or potential targets for treatment are needed. Loss of BRCA associated protein-1 (BAP1) expression has been found in up to a quarter of intrahepatic cholangiocarcinomas. Given the close anatomical relationship between intrahepatic cholangiocarcinoma and pancreatic ductal adenocarcinoma, we therefore sought to investigate the frequency of loss of BAP1 expression in pancreatic ductal adenocarcinoma.Methods
The records of the department of Anatomical Pathology Royal North Shore Hospital, Sydney, Australia, were searched for cases of pancreatic ductal adenocarcinoma diagnosed between 1992 and 2014 with material available in archived formalin fixed paraffin embedded tissue blocks. Immunohistochemistry for BAP1 was performed on tissue microarray sections and if staining was equivocal or negative it was confirmed on whole sections. Negative staining for BAP1 was defined as loss of expression in all neoplastic nuclei, with preserved expression in non-neoplastic cells which acted as an internal positive control.Results
Loss of BAP1 expression was found in only 1 of 306 (0.33%) pancreatic ductal adenocarcinomas. This case was confirmed to demonstrate diffuse loss of expression throughout all neoplastic cells in multiple blocks, consistent with BAP1 loss being an early clonal event. All other cases demonstrated positive expression of BAP1.Conclusion
We conclude that, in contrast to intrahepatic cholangiocarcinoma, loss of expression of BAP1 occurs very rarely in pancreatic ductal adenocarcinoma. Therefore BAP1 inactivation is unlikely to be a frequent driver abnormality in pancreatic adenocarcinoma. 相似文献959.
Alan Maldonado-Márquez Tamara Contador Javier Rendoll-Cárcamo Sabrina Moore Carolina Pérez-Troncoso Daniel Gomez-Uchida Chris Harrod 《Journal of fish biology》2020,96(6):1495-1500
The Cape Horn Biosphere Reserve, one of the last wild areas of the planet, is not exempt from the pressures of global change, such as non-native species introductions. During 2018 and 2019 we studied the Róbalo river basin in order to update the diversity and distribution of fishes. Here, we report for the first time the native and endangered “Peladillas” Aplochiton taeniatus and the non-native coho salmon Oncorhynchus kisutch. The coexistence of native and non-native fishes poses a challenge for the management and conservation of aquatic biota from the Cape Horn Biosphere Reserve. 相似文献
960.
Nicholas Matluk Jennifer A Rochira Aldona Karaczyn Tamara Adams Joseph M Verdi 《BMC biology》2010,8(1):7