21 research outputs found
Dynamical restriction for a growing neck due to mass parameters in a dinuclear system
Mass parameters for collective variables of a dinuclear system and strongly
deformed mononucleus are microscopically formulated with the linear response
theory making use of the width of single particle states and the
fluctuation-dissipation theorem. For the relative motion of the nuclei and for
the degree of freedom describing the neck between the nuclei, we calculate mass
parameters with basis states of the adiabatic and diabatic two-center shell
model. Microscopical mass parameters are found larger than the ones obtained
with the hydrodynamical model and give a strong hindrance for a melting of the
dinuclear system along the internuclear distance into a compound system.
Therefore, the dinuclear system lives a long time enough comparable to the
reaction time for fusion by nucleon transfer. Consequences of this effect for
the complete fusion process are discussed.Comment: 22 pages, 7 figures, submitted to Nucl.Phys.
Discordance between patients ́ and physicians ́ beliefs regarding barriers to HIV treatment initiation
info:eu-repo/semantics/nonPublishe
Reasons for not starting antiretroviral therapy: A multinational survey among patients and their physicians
info:eu-repo/semantics/nonPublishe
Chronic Kidney Disease and Exposure to ART in a large cohort with Long-term Follow-up: The EuroSIDA study
For the EuroSIDA study Groupinfo:eu-repo/semantics/nonPublishe
Elevated CO2 levels and herbivore damage alter host plant preferences
Interactions between the moth Spodoptera littoralis and two of its host plants, alfalfa (Medicago sativa) and cotton (Gossypium hirsutum) were examined, using plants grown under ambient (350 ppm) and elevated (700 ppm) CO2 conditions. To determine strength and effects of herbivore-induced responses assays were performed with both undamaged (control) and herbivore damaged plants. CO2 and damage effects on larval host plant preferences were determined through dual-choice bioassays. In addition, larvae were reared from hatching to pupation on experimental foliage to examine effects on larval growth and development. When undamaged plants were used S. littoralis larvae in consumed more cotton than alfalfa, and CO2 enrichment caused a reduction in the preference for cotton. With damaged plants larvae consumed equal amounts of the two plant species (ambient CO2 conditions), but CO2 enrichment strongly shifted preferences towards cotton, which was then consumed three times more than alfalfa. Complementary assays showed that elevated CO2 levels had no effect on the herbivore-induced responses of cotton, whereas those of alfalfa were significantly increased. Larval growth was highest for larvae fed undamaged cotton irrespectively of CO2 level, and lowest for larvae on damaged alfalfa from the high CO2 treatment. Development time increased on damaged cotton irrespectively of CO2 treatment, and on damaged alfalfa in the elevated CO2 treatment. These results demonstrate that elevated CO2 levels can cause insect herbivores to alter host plant preferences, and that effects on herbivore-induced responses may be a key mechanism behind these processes. Furthermore, since the insects were shown to avoid foliage that reduced their physiological performance, our data suggest that behavioural host plant shifts result in partial escape from negative consequences of feeding on high CO2 foliage. Thus, CO2 enrichment can alter both physiology and behaviour of important insect herbivores, which in turn may to impact plant biodive