Search results for "MECHANISMS"
showing 10 items of 587 documents
Role of dioxygenase α-DOX2 and SA in basal response and in hexanoic acid-induced resistance of tomato (Solanum lycopersicum) plants against Botrytis …
2015
Resistance of tomato (Solanum Lycopersicum) to the fungal pathogen Botrytis cinerea requires complex interplay between hormonal signalling. In this study, we explored the involvement of new oxylipins in the tomato basal and induced response to this necrotroph through the functional analysis of the tomato α-dioxygenase2 (α-DOX2)-deficient mutant divaricata. We also investigated the role of SA in the defence response against this necrotrophic fungus using SA-deficient tomato nahG plants. The plants lacking dioxigenase α-DOX2, which catalyses oxylipins production from fatty acids, were more susceptible to Botrytis, and hexanoic acid-induced resistance (Hx-IR) was impaired; hence α-DOX2 is requ…
Do the benefits of polyandry scale with outbreeding?
2015
Lay Summary Mating can be both costly and dangerous. Despite this, females of many species typically mate more than once and with different males. We found that female seed bugs only benefit from mating with more than 1 male if one of her mates was a different species. Females needed only 1 mating with her own species to maximize her fitness. Thus, multiple mating may be adaptive in areas where the 2 species coexist.
Fecundity determines the outcome of founding queen associations in ants
2021
AbstractAnimal cooperation evolved because of its benefits to the cooperators. Pleometrosis in ants - the cooperation of queens to found a colony - benefits colony growth, but also incurs costs for some of the cooperators because only one queen usually survives the association. While several traits are associated with queen survival, they tend to be confounded and it is unclear which factor specifically determines the outcome of pleometrosis. In this study, we used the ant Lasius niger to monitor offspring production in colonies founded by one or two queens. Then, we experimentally paired queens that differed in fecundity but not in size, and vice versa, to disentangle the effect of these f…
Activation of Grapevine Defense Mechanisms: Theoretical and Applied Approaches
2011
part 4.; International audience; Grapevine, as other plants, possesses an innate immune system that usually prevents infection by pathogens. General elicitors are compounds of different biochemical families capable of inducing plant defense reactions. In grapevine, the cascade of defense events induced by elicitors has been studied among others in cell suspensions. The perception of the elicitor triggers signaling events that allow the activation of defense genes encoding PR proteins and other proteins involved in phytoalexin production and cell wall reinforcement. The grapevine phytoalexins resveratrol and derivated compounds have been largely studied. In addition to their antimicrobial ac…
Data from: Predators’ consumption of unpalatable prey does not vary as a function of bitter taste perception
2019
Many prey species contain defensive chemicals that are described as tasting bitter. Bitter taste perception is therefore assumed to be important when predators are learning about prey defenses. However, it is not known how individuals differ in their response to bitter taste, and how this influences their foraging decisions. We conducted taste perception assays in which wild-caught great tits (Parus major) were given water with increasing concentrations of bitter-tasting chloroquine diphosphate until they showed an aversive response to bitter taste. This response threshold was found to vary considerably among individuals, ranging from chloroquine concentrations of 0.01 mmol/l to 8 mmol/l. W…
Determination of pesticide residues in honey bees, pollen and beeswax: assessing pesticide hazard in spanish apiaries
2020
Pollinator decline is an emerging worldwide problem with serious repercussions on agriculture and environment. Around one third of human food relies on insect pollination, and most of the flowering plants need pollinators to survive. Honey bee is the main pollinator in environments where anthropogenic pressure has reduced the number of native pollinators, like urban, rural and agricultural areas. The main cause of beekeeping crisis is parasite Varroa destructor and secondary infections associated with the mite. Pesticide contamination and nutritional deficiencies, combined with the parasite, can act synergistically and reduce survival of bee colonies. Honey bees patrol extensive areas when …
Humanoid Cognitive Robots That Learn by Imitating: Implications for Consciousness Studies.
2018
While the concept of a conscious machine is intriguing, producing such a machine remains controversial and challenging. Here we describe how our work on creating a humanoid cognitive robot that learns to perform tasks via imitation learning relates to this issue. Our discussion is divided into three parts. First, we summarize our previously-detailed framework for advancing the understanding of the nature of phenomenal consciousness. This framework is based on identifying computational correlates of consciousness. Second, we describe a cognitive robotic system that we recently developed that learns to perform tasks by imitating human-provided demonstrations. This humanoid robot uses cause-ef…
Reflexiones sobre la concurrencia de violencia económica en el contexto de familia : impacto y mecanismos para su neutralización
2021
Through this work we carry out a dissertation on the phenomenon of economic violence, as a manifestation of gender violence, in the family context, and, especially, from the perspective of the divorce framework. We will analyze the harmful effects that it produces, the damage that it triggers on the most basic and essential interests of the family, and its use as a control mechanism by the aggressors. In addition to a vision of the different mechanisms that, enshrined in our legal system, serve to distort it.
An X-ray characterization of the central region of the supernova remnant G332.5-5.6
2015
Aims. We present an X-ray analysis of the central region of supernova remnant (SNR) G332.5-5.6 through an exhaustive analysis of XMM-Netwon observations with complementary infrared observations. We characterize and discuss the origin of the observed X-ray morphology, which presents a peculiar plane edge over the west side of the central region. Methods. The morphology and spectral properties of the X-ray SNR were studied using a single full frame XMM-Netwon observation in the 0.3 to 10.0 keV energy band. Archival infrared WISE observations at 8, 12 and 24 μm were also used to investigate the properties of the source and its surroundings at different wavelengths. Results. The results show th…
On the location of the supermassive black hole in CTA102
2015
Relativistic jets in active galactic nuclei represent one of the most powerful phenomena in the Universe. They form in the surroundings of the supermassive black holes as a by-product of accretion onto the central black hole in active galaxies. The flow in the jets propagates at velocities close to the speed of light. The distance between the first part of the jet that is visible in radio images (core) and the black hole is still a matter of debate. Only very-long-baseline interferometry observations resolve the innermost compact regions of the radio jet. Those can access the jet base, and combining data at different wavelenghts, address the physical parameters of the outflow from its emiss…