Search results for "limited"
showing 10 items of 177 documents
Happy and proactive ?:The role of hedonic and eudaimonic well-being in business owners’ personal initiative
2012
This two-year study with 122 business owners examined the link between affective well-being and task-oriented as well as relationship-oriented personal initiative (PI). We tested two complementary models explaining the link between well-being and PI: (1) broaden-and-build theory and (2) self-regulation as limited resource approach. In line with current research on well-being, we differentiated between hedonic and eudaimonic well-being using life satisfaction and vigor as indicators. Hierarchical regression analyses showed that only vigor predicted both forms of PI. Our results support the self-regulation approach and indicate that eudaimonic well-being is the relevant affective well-being d…
Insect Vectors (Hemiptera: Cixiidae) and Pathogens Associated with the Disease Syndrome “Basses Richesses” of Sugar Beet in France
2019
International audience; The syndrome “basses richesses” (SBR) is a disease of sugar beet in eastern France associated with two phloem-restricted, nonculturable plant pathogens: a stolbur phytoplasma and a γ-3 proteobacterium, here called SBR bacterium. Three planthopper (Hemiptera: Cixiidae) species were found to live near and within sugar beet fields in eastern France: Cixius wagneri, Hyalesthes obsoletus, and Pentastiridius leporinus. The role of these planthoppers in spreading the two pathogens to sugar beet was studied. Based on its abundance and high frequency of infection with the SBR bacterium, P. leporinus was considered to be the economic vector of SBR disease. C. wagneri, the prim…
Evolution of sexually dimorphic pheromone profiles coincides with increased number of male‐specific chemosensory organs in Drosophila prolongata
2019
Abstract Binary communication systems that involve sex‐specific signaling and sex‐specific signal perception play a key role in sexual selection and in the evolution of sexually dimorphic traits. The driving forces and genetic changes underlying such traits can be investigated in systems where sex‐specific signaling and perception have emerged recently and show evidence of potential coevolution. A promising model is found in Drosophila prolongata, which exhibits a species‐specific increase in the number of male chemosensory bristles. We show that this transition coincides with recent evolutionary changes in cuticular hydrocarbon (CHC) profiles. Long‐chain CHCs that are sexually monomorphic …
Eliciting expert knowledge to inform stock status for data-limited stock assessments
2019
Data-limited fisheries are a major challenge for stock assessment analysts, as many traditional data-rich models cannot be implemented. Approaches based on stock reduction analysis offer simple ways to handle low data availability, but are particularly sensitive to assumptions on relative stock status (i.e., current biomass compared to unperturbed biomass). For the vast majority of data-limited stocks, stock status is unmeasured. The present study presents a method to elicit expert knowledge to inform stock status and a novel, user-friendly on-line application for expert elicitation. Expert opinions are compared to stock status derived from data-rich models. Here, it is evaluated how expert…
Bivalve shell formation in a naturally CO2-enriched habitat: Unraveling the resilience mechanisms from elemental signatures
2018
Abstract Marine bivalves inhabiting naturally pCO2-enriched habitats can likely tolerate high levels of acidification. Consequently, elucidating the mechanisms behind such resilience can help to predict the fate of this economically and ecologically important group under near-future scenarios of CO2-driven ocean acidification. Here, we assess the effects of four environmentally realistic pCO2 levels (900, 1500, 2900 and 6600 μatm) on the shell production rate of Mya arenaria juveniles originating from a periodically pCO2-enriched habitat (Kiel Fjord, Western Baltic Sea). We find a significant decline in the rate of shell growth as pCO2 increases, but also observe unchanged shell formation r…
Simple learning rules to cope with changing environments
2008
10 pages; International audience; We consider an agent that must choose repeatedly among several actions. Each action has a certain probability of giving the agent an energy reward, and costs may be associated with switching between actions. The agent does not know which action has the highest reward probability, and the probabilities change randomly over time. We study two learning rules that have been widely used to model decision-making processes in animals-one deterministic and the other stochastic. In particular, we examine the influence of the rules' 'learning rate' on the agent's energy gain. We compare the performance of each rule with the best performance attainable when the agent …
Dynamics of PHA-induced immune response and plasma carotenoids in birds: should we have a closer look?
2009
SUMMARY Allocation trade-offs of limited resources are thought to ensure the honesty of sexual signals and are often studied using controlled immune challenges. One such trade-off between immunity and ornaments is that involving carotenoids. Phytohemagglutinin (PHA)-induced immune response is a widely used immune challenge, yet more details on the underlying physiological mechanisms and potential costs are needed. We investigated the temporal dynamics of PHA-induced immune response and associated changes in blood carotenoids, body mass and a carotenoid-based coloured signal. We found variation in individual response patterns to PHA after peak swelling was reached, with birds showing either …
Context-dependent coloration of prey and predator decision making in contrasting light environments
2022
A big question in behavioral ecology is what drives diversity of color signals. One possible explanation is that environmental conditions, such as light environment, may alter visual signaling of prey, which could affect predator decision-making. Here, we tested the context-dependent predator selection on prey coloration. In the first experiment, we tested detectability of artificial visual stimuli to blue tits (Cyanistes caeruleus) by manipulating stimulus luminance and chromatic context of the background. We expected the presence of the chromatic context to facilitate faster target detection. As expected, blue tits found targets on chromatic yellow background faster than on achromatic gre…
Need for Deprescribing in Hospital Elderly Patients Discharged with a Limited Life Expectancy: The REPOSI Study
2019
<b><i>Objective:</i></b> Older people approaching the end of life are at a high risk for adverse drug reactions. Approaching the end of life should change the therapeutic aims, triggering a reduction in the number of drugs.<b><i></i></b>The main aim of this study is to describe the preventive and symptomatic drug treatments prescribed to patients discharged with a limited life expectancy from internal medicine and geriatric wards. The secondary aim was to describe the potentially severe drug-drug interactions (DDI). <b><i>Materials and Methods:</i></b> We analyzed Registry of Polytherapies Societa Italiana di Medicina I…
Adjuvant MUC vaccination with tecemotide after resection of colorectal liver metastases: a randomized, double-blind, placebo-controlled, multicenter …
2020
ABSTRACT Resection of colorectal liver metastases (CRLM) is a potential curative treatment for patients with metastatic colorectal cancer (mCRC) with liver-limited disease (LLD). Although long-term survival improved considerably within the last decades, high recurrence rates of 50-75% after resection remain a major challenge.Tecemotide (L-BLP25) is an antigen-specific cancer vaccine inducing immunity against mucin-1 (MUC1). The LICC trial aimed to improve survival in patients with mCRC after R0/R1 resection of CRLM. LICC was a binational, randomized, double-blind, placebo-controlled, multicenter phase 2 study including patients with R0/R1 resected CRLM without evidence of metastatic disease…