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991.
Christina Alba M. Deane Bowers Dana Blumenthal Ruth Hufbauer 《Biological invasions》2011,13(10):2379-2389
Post-introduction evolution of increased growth or reproduction has been observed in many species of invasive plants; however,
it is not consistently associated with a loss of defense, as predicted by the influential evolution of increased competitive ability (EICA) hypothesis. Inconsistent support for the EICA hypothesis likely reflects the fact that, although invasive plants are
released from attack by some enemies, typically specialists, they often do not escape attack from generalists. Thus, different
types of defense (e.g., structural versus chemical) may evolve in different directions following introduction. We used a common
garden experiment to test whether a shift in allocation among defenses (as opposed to a simple increase or decrease in a single
defense) is associated with increased growth in introduced Verbascum thapsus populations. Introduced populations had significantly greater shoot biomass than natives. However, root biomass was similar
between ranges, and highly variable, resulting in only marginal differences in total biomass. Mean investment in all three
defenses was remarkably similar between the native and introduced populations, providing no evidence for range-level, post-introduction
evolution of defense. This finding was consistent with the fact that, despite significant population-level variability for
all defenses, there was little evidence of trade-offs between growth and defense or among different types of defense. These
results suggest that evolution of increased growth in V. thapsus is not fueled by decreased allocation to defense, and that selection on defense may vary more at the population scale than
the continental scale. 相似文献
992.
The drug trade,crime and policies of repression in Brazil 总被引:1,自引:0,他引:1
Alba Zaluar 《Dialectical Anthropology》1995,20(1):95-108
993.
Agulló Melania Heras Sandra García-Marín José-Luis Vera Manuel Abras Alba Planella Laia Roldán María Inés 《Hydrobiologia》2022,849(9):2043-2055
Hydrobiologia - The blue and red shrimp Aristeus antennatus has been intensively exploited by trawling fishery in the Western Mediterranean Sea. Implementation of an adequate management plan needs... 相似文献
994.
Cinta Llibre Elisabet Zamora Àngel Caballero Josep Lupón Alba Ros Nuria Benito 《Biomarkers》2016,21(3):225-232
Context: Prognostic value of ST2 levels and dynamics has not been investigated in acute heart failure (AHF) using prospective real-life measurements.Objective: The objective of this study is to investigate the prognostic value of ST2 in AHF.Methods: ST2 levels were determined at admission (n?=?182) and discharge (n?=?85). Primary endpoint was the composite of all-cause death and HF rehospitalisation at one year.Results: Discharge ST2 (HR 2.42 [95% CI 1.46–4], p?=?0.001) and ΔST2 (HR 2.32 [95% CI 1.21–4.57], p?=?0.01) but not admission ST2, remained independently prognostic for the primary endpoint after comprehensive multivariable adjustment. ST2 significantly improved prognosis stratification on top of clinical variables and NTproBNP.Conclusions: Routine clinical use of discharge ST2 and ST2 dynamics provide independent prognostic information. 相似文献
995.
Nieves García-Quintans Ignacio Baquedano Alba Blesa Carlos Verdú José Berenguer Mario Mencía 《Environmental microbiology》2020,22(11):4647-4657
Primase-polymerases (Ppol) are one of the few enzymes able to start DNA synthesis on ssDNA templates. The role of Thermus thermophilus HB27 Ppol, encoded along a putative helicase (Hel) within a mobile genetic element (ICETh2), has been studied. A mutant lacking Ppol showed no effects on the replication of the element. Also, no apparent differences in the sensitivity to DNA damaging agents and other stressors or morphological changes in the mutant cells were detected. However, the mutants lacking Ppol showed an increase in two to three orders of magnitude in their transformation efficiency with plasmids and genomic DNA acquired from the environment (eDNA), independently of its origin and G + C content. In contrast, no significant differences with the wild type were detected when the cells received the DNA from other T. thermophilus partners in conjugation-like mating experiments. The similarities of this behaviour with that shown by mutants lacking the Argonaute (ThAgo) protein suggests a putative partnership Ppol-ThAgo in the DNA–DNA interference mechanism of defence, although other eDNA defence mechanisms independent of ThAgo cannot be discarded. 相似文献
996.
Chiaraluce Moretti Fabio Rezzonico Benedetta Orfei Chiara Cortese Alba Moreno-Pérez Harrold A. van den Burg Andrea Onofri Giuseppe Firrao Cayo Ramos Theo H. M. Smits Roberto Buonaurio 《Molecular Plant Pathology》2021,22(10):1209-1225
The endophytic bacterium Pantoea agglomerans DAPP-PG 734 was previously isolated from olive knots caused by infection with Pseudomonas savastanoi pv. savastanoi DAPP-PG 722. Whole-genome analysis of this P. agglomerans strain revealed the presence of a Hypersensitive response and pathogenicity (Hrp) type III secretion system (T3SS). To assess the role of the P. agglomerans T3SS in the interaction with P. savastanoi pv. savastanoi, we generated independent knockout mutants in three Hrp genes of the P. agglomerans DAPP-PG 734 T3SS (hrpJ, hrpN, and hrpY). In contrast to the wildtype control, all three mutants failed to cause a hypersensitive response when infiltrated in tobacco leaves, suggesting that P. agglomerans T3SS is functional and injects effector proteins in plant cells. In contrast to P. savastanoi pv. savastanoi DAPP-PG 722, the wildtype strain P. agglomerans DAPP-PG 734 and its Hrp T3SS mutants did not cause olive knot disease in 1-year-old olive plants. Coinoculation of P. savastanoi pv. savastanoi with P. agglomerans wildtype strains did not significantly change the knot size, while the DAPP-PG 734 hrpY mutant induced a significant decrease in knot size, which could be complemented by providing hrpY on a plasmid. By epifluorescence microscopy and confocal laser scanning microscopy, we found that the localization patterns in knots were nonoverlapping for P. savastanoi pv. savastanoi and P. agglomerans when coinoculated. Our results suggest that suppression of olive plant defences mediated by the Hrp T3SS of P. agglomerans DAPP-PG 734 positively impacts the virulence of P. savastanoi pv. savastanoi DAPP-PG 722. 相似文献
997.
R. Borja J. Alba A. Mancha A. Martín V. Alonso E. Sánchez 《Bioprocess and biosystems engineering》1998,18(2):127-134
A comparative kinetic study was carried out on the anaerobic digestion of olive mill wastewater (OMW) and OMW that was previously fermented with Geotrichum candidum, Azotobacter chroococcum and Aspergillus terreus. The reactors used were continuously fed and contained sepiolite as support for the mediating bacteria. A kinetic model for multicomponent substrate removal by anaerobic digestion has been used. The model is based on the linear removal concept which is a special case of the broader Monod equation. The second-order kinetic constant, k 2( s ), was found to be influenced by the pretreatment carried out, and was 4.2, 4.0 and 2.5 times higher for Aspergillus, Azotobacter and Geotrichum-pretreated OMWs than that obtained in the anaerobic digestion of untreated OMW. This was significant at 95% confidence level. This behaviour is believed to be due to the lower levels of phenolic compounds and biotoxicity present in the pretreated OMWs. In fact, the kinetic constant increased when the phenolic compound content and biotoxicity of the pretreated OMWs decreased. In addition, the macroenergetic parameters of the anaerobic digestion of OMW, i.e. the specific rate of substrate uptake for cell maintenance, m, and the yield coefficient for the biomass, Y, decreased by a factor of 2.4, 3.6 and 5.1 and increased by a factor of 1.9, 2.2 and 2.4 respectively, for the OMWs previously treated with Geotrichum candidum, Azotobacter chroococcum and Aspergillus terreus in relation to the observed values for the untreated OMW. 相似文献
998.
999.
1000.
Sara Blicharz Gerrit T.S. Beemster Laura Ragni Nuria De Diego Lukas Spíchal Alba E. Hernándiz Łukasz Marczak Marcin Olszak Dawid Perlikowski Arkadiusz Kosmala Robert Malinowski 《The Plant journal : for cell and molecular biology》2021,106(5):1338-1355
Drought stress impacts the quality and yield of Pisum sativum. Here, we show how short periods of limited water availability during the vegetative stage of pea alters phloem sap content and how these changes are connected to strategies used by plants to cope with water deficit. We have investigated the metabolic content of phloem sap exudates and explored how this reflects P. sativum physiological and developmental responses to drought. Our data show that drought is accompanied by phloem-mediated redirection of the components that are necessary for cellular respiration and the proper maintenance of carbon/nitrogen balance during stress. The metabolic content of phloem sap reveals a shift from anabolic to catabolic processes as well as the developmental plasticity of P. sativum plants subjected to drought. Our study underlines the importance of phloem-mediated transport for plant adaptation to unfavourable environmental conditions. We also show that phloem exudate analysis can be used as a useful proxy to study stress responses in plants. We propose that the decrease in oleic acid content within phloem sap could be considered as a potential marker of early signalling events mediating drought response. 相似文献