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1.
Sci Rep ; 14(1): 6128, 2024 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-38480802

RESUMO

The stronger people hold self-enhancing (that is, egoistic or hedonic) values, the less they tend agree with pro-environmental efforts. An exploratory (N = 901) and a confirmatory study (N = 404) examined the effectiveness of pro-environmental messages matched to individuals' values. Findings indicate that strong endorsement of self-transcendent (that is, altruistic or biospheric) values is associated with unspecific endorsement of pro-environmental messages, while individuals endorsing self-enhancement values respond positively only to value-matched appeals.


Assuntos
Altruísmo , Mudança Climática , Humanos
2.
Ecol Evol ; 14(3): e11061, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38455145

RESUMO

Land-use management is a key factor causing pollinator declines in agricultural grasslands. This decline can not only be directly driven by land-use (e.g., habitat loss) but also be indirectly mediated through a reduction in floral resource abundance and diversity, which might in turn affect pollinator health and foraging. We conducted surveys of the abundance of flowering plant species and behavioural observations of two common generalist pollinator species, namely the bumblebee Bombus lapidarius and the syrphid fly Episyrphus balteatus, in managed grasslands of variable land-use intensity (LUI) to investigate whether land-use affects (1) resource availability of the pollinators, (2) their host plant selection and (3) pollinator foraging behaviour. We have found that the floral composition of plant species that were used as resource by the investigated pollinator species depends on land-use intensity and practices such as mowing or grazing. We have also found that bumblebees, but not syrphid flies, visit different plants depending on LUI or management type. Furthermore, LUI indirectly changed pollinator behaviour via a reduction in plot-level flower diversity and abundance. For example, bumblebees show longer flight durations with decreasing flower cover indicating higher energy expenditure when foraging on land-use intensive plots. Syrphid flies were generally less affected by local land use, showing how different pollinator groups can differently react to land-use change. Overall, we show that land-use can change resource composition, abundance and diversity for pollinators, which can in turn affect pollinator foraging behaviour and potentially contribute to pollinator decline in agricultural grasslands.

3.
Proc Biol Sci ; 290(2008): 20231322, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37817596

RESUMO

In agricultural landscapes, bees face a variety of stressors, including insecticides and poor-quality food. Although both stressors individually have been shown to affect bumblebee health negatively, few studies have focused on stressor interactions, a scenario expected in intensively used agricultural landscapes. Using the bumblebee Bombus terrestris, a key pollinator in agricultural landscapes, we conducted a fully factorial laboratory experiment starting at nest initiation. We assessed the effects of food quality and insecticides, alone and in interaction, on health traits at various levels, some of which have been rarely studied. Pollen with a diluted nutrient content (low quality) reduced ovary size and delayed colony development. Wing asymmetry, indicating developmental stress, was increased during insecticide exposure and interactions with poor food, whereas both stressors reduced body size. Both stressors and their interaction changed the workers' chemical profile and reduced worker interactions and the immune response. Our findings suggest that insecticides combined with nutritional stress reduce bumblebee health at the individual and colony levels, thus possibly affecting colony performance, such as development and reproduction, and the stability of plant-pollinator networks. The synergistic effects highlight the need of combining stressors in risk assessments and when studying the complex effects of anthropogenic stressors on health outcomes.


Assuntos
Inseticidas , Feminino , Abelhas , Animais , Inseticidas/farmacologia , Reprodução , Pólen , Agricultura , Alimentos
4.
Sci Rep ; 13(1): 8865, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37258562

RESUMO

Vaccination rates are still insufficient to prevent the spread of COVID-19, so immunity must be increased among the population in order to reduce the virus' spread and the associated medical and psychosocial effects. Although previous work has identified various factors associated with a low willingness to get vaccinated, the role of emotions such as fear of vaccination (FVAC) or fear of COVID-19 (FCOV), vaccination as a subjective norm (SN), psychological factors like general control beliefs (CB) or psychological resilience, and their interaction have been investigated less intensively. We used data from three cross-sectional waves of the German Panel COSMO (November 2021, N = 1010; February 2022, N = 1026; March 2022, N = 1031) and multiple logistic regression analyses to test whether vaccination rates are moderated by those factors. After controlling for covariates (age, sex, confidence in own intuition, optimism, well-being), we found that CB was no significant predictor of vaccination status. Higher FCOV and higher ratings in SN, however, were associated with an increased likelihood of being vaccinated. In contrast, higher FVAC was associated with a decreased likelihood of being vaccinated. Psychological resilience did not consistently moderate the associations between fear and vaccination status.


Assuntos
COVID-19 , Humanos , Estudos Transversais , COVID-19/epidemiologia , COVID-19/prevenção & controle , Medo , Emoções , Vacinação
5.
Ecol Evol ; 11(24): 17973-17999, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35003651

RESUMO

Tree hollows are among the rarest habitats in today's Central European managed forests but are considered key structures for high biodiversity in forests. To analyze and compare the effects of tree hollow characteristics and forest structure on diversity of saproxylic beetles in tree hollows in differently structured managed forests, we examined between 41 and 50 tree hollows in beech trees in each of three state forest management districts in Germany. During the two-year study, we collected 283 saproxylic beetle species (5880 individuals; 22% threatened species), using emergence traps. At small spatial scales, the size of hollow entrance and the number of surrounding microhabitat structures positively influenced beetle diversity, while the stage of wood mould decomposition had a negative influence, across all three forest districts. We utilized forest inventory data to analyze the effects of forest structure in radii of 50-500 m around tree hollows on saproxylic beetle diversity in the hollows. At these larger spatial scales, the three forest management districts differed remarkably regarding the parameters that influenced saproxylic beetle diversity in tree hollows. In Ebrach, characterized by mostly deciduous trees, the amount of dead wood positively influenced beetle diversity. In the mostly coniferous Fichtelberg forest district, with highly isolated tree hollows, in contrast, only the proportion of beech trees around the focal tree hollows showed a positive influence on beetle diversity. In Kelheim, characterized by mixed forest stands, there were no significant relationships between forest structure and beetle diversity in tree hollows. In this study, the same local tree hollow parameters influenced saproxylic beetle diversity in all three study regions, while parameters of forest structure at larger spatial scales differed in their importance, depending on tree-species composition.

6.
Front Zool ; 14: 26, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28533810

RESUMO

BACKGROUND: Stem cells are undifferentiated cells with a potential for self-renewal, which are essential to support normal development and homeostasis. To gain insight into the molecular mechanisms underlying adult stem cell biology and organ evolution, we use the telotrophic ovary of the beetle Tribolium. To this end, we participated in a large-scale RNAi screen in the red flour beetle Tribolium, which identified functions in embryonic and postembryonic development for more than half of the Tribolium genes. RESULTS: We identified TC003132 as candidate gene for the follicle stem cell linage in telotrophic Tribolium oogenesis. TC003132 belongs to the Casein Kinase 2 substrate family (CK2S), which in humans is associated with the proliferative activity of different cancers. Upon TC003132 RNAi, central pre-follicular cells are lost, which results in termination of oogenesis. Given that also Notch-signalling is required to promote the mitotic activity of central pre-follicular cells, we performed epistasis experiments with Notch and cut. In addition, we identified a putative follicle stem cell population by monitoring the mitotic pattern of wild type and TC003132 depleted follicle cells by EdU incorporations. In TC003132 RNAi these putative FSCs cease the expression of differentiation makers and are eventually lost. CONCLUSIONS: TC003132 depleted pre-follicular cells neither react to mitosis or endocycle stimulating signals, suggesting that TC003132 provides competence for differentiation cues. This may resemble the situation in C. elegans were CK2 is required to maintain the balance between proliferation and differentiation in the germ line. Since the earliest effect of TC003132 RNAi is characterized by the loss of putative FSCs, we posit that TC003132 crucially contributes to the proliferation or maintenance of follicle stem cells in the telotrophic Tribolium ovary.

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