Behavioural innovation, the use of new behaviours or existing ones in novel contexts, can have important ecological and evolutionary consequences for animals. An understanding of these consequences ...would be incomplete without considering the traits that predispose certain individuals to exhibit innovative behaviour. Several individual and ecological variables are hypothesized to affect innovativeness, but empirical studies show mixed results. We examined the effects of dominance rank, exploratory personality, and urbanisation on the innovativeness of wild-caught black-capped chickadees using a survival analysis of their performance in two problem-solving tasks. Additionally, we provide one of the first investigations of the predictors of persistence in a problem-solving context. For lever pulling, we found a trend for dominants to outperform subordinates, particularly in rural birds, which did not align with predictions from the necessity drives innovation hypothesis. When examining possible explanations for this trend we found that older chickadees outperformed younger birds. This follow-up analysis also revealed a positive effect of exploratory personality on the lever-pulling performance of chickadees. Our results suggest that experience may foster innovation in certain circumstances, for instance via the application of previously-acquired information or skills to a novel problem. As we found different predictors for both tasks, this suggests that task characteristics influence the innovative propensity of individuals, and that their effects should be investigated experimentally.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Urban agriculture is increasingly valued as a strategy for improving quality of life in cities, but urban growers face challenges and often lack coordinated support from governments and the ...agricultural industry. We surveyed urban growers through an online survey, primarily in the Northeastern United States, to develop a profile of growers and associated organizations, assess the current state of urban agriculture, and determine how universities could help meet their needs. A total of 394 respondents completed the survey and most urban growers were white (non-Hispanic) and younger than 45 years old. Women and men were in almost equal proportion. Urban growers were well-educated, but most did not receive a degree in agriculture. Urban agriculture in our study area was dominated by relatively small non-profit organizations and home and community gardens were the most common types of organizations. Urban agricultural organizations want to improve environmental sustainability and socio-cultural conditions through food access and security, regardless of their tax status. Urban growers face diverse barriers and challenges and the most ubiquitous barriers and challenges reported by respondents were related to availability of land and long-term access in urban areas. Many respondents received low revenue or were operating at a net loss even though they reported diverse income streams. Respondents need a wide range of training, including in traditional agricultural topics as well as financial management and business trainings. Universities can play a key role in promoting urban agriculture by offering training and research. Workforce development is a large priority among universities, so urban growers should regularly be consulted, and the results shared with career and workforce development professionals and researchers in urban areas to identify training and research that meets the needs of stakeholders.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Adults over 65 years of age are more vulnerable to infectious disease and show poor responses to vaccination relative to those under 50. A complex set of age-related changes in the immune system is ...believed to be largely responsible for these defects. These changes, collectively termed immune senescence, encompass alterations in both the innate and adaptive immune systems, in the microenvironments where immune cells develop or reside, and in soluble factors that guide immune homeostasis and function. While age-related changes in primary lymphoid organs (bone marrow, and, in particular, the thymus, which involutes in the first third of life) have been long appreciated, changes affecting aging secondary lymphoid organs, and, in particular, aging lymph nodes (LNs) have been less well characterized. Over the last 20 years, LN stromal cells have emerged as key players in maintaining LN morphology and immune homeostasis, as well as in coordinating immune responses to pathogens. Here, we review recent progress in understanding the contributions of LN stromal cells to immune senescence. We discuss approaches to understand the mechanisms behind the decline in LN stromal cells and conclude by considering potential strategies to rejuvenate aging LN stroma to improve immune homeostasis, immune responses, and vaccine efficacy in the elderly.
Urbanization has been shown to affect the physiological, morphological, and behavioral traits of animals, but it is less clear how cognitive traits are affected. Urban habitats contain artificial ...food sources, such as bird feeders that are known to impact foraging behaviors. As of yet, however, it is not well known whether urbanization and the abundance of supplemental food during the winter affect caching behaviors and spatial memory in scatter hoarders. We aim to compare caching intensity and spatial memory performance along an urban gradient to determine (i) whether individuals from more urbanized sites cache less frequently and perform less accurately on a spatial memory task, and (ii) for the first time in individual scatter hoarders, whether slower explorers perform more accurately than faster explorers on a spatial memory task. We assessed food caching, exploration of a novel environment, and spatial memory performance of wild-caught black-capped chickadees (
Poecile atricapillus
;
N
= 95) from 14 sites along an urban gradient. Although the individuals that cached most in captivity were all from less urbanized sites, we found no clear evidence that caching intensity and spatial memory accuracy differed along an urban gradient. At the individual level, we found no significant relationship between spatial memory performance and exploration score. However, individuals that performed more accurately on the spatial task also tended to cache more, pointing to a specialization of spatial memory in scatter hoarders that could occur at the level of the individual, in addition to the previously documented specialization at the population and species levels.
Developments during adolescence increase risk for sleep problems. Research in adults suggests mindfulness and sleep are associated, with two different theoretical explanations for direction of ...effects. Our goal was to directly test these competing theoretical models at the daily level in adolescents using objective and self-reported measurements of sleep. Adolescents (N = 138; 14–21 yrs) reported mindful attention and sleep for a week, while wearing an actigraph. Results indicated that, within-person, poor sleep at night predicted less mindful attention the next day; however, mindful attention during the day did not predict sleep that night. These findings provide support for the developmental model of sleep and regulation and suggest poor sleep may impair regulatory abilities the following day.
Cities pose a major ecological challenge for wildlife worldwide. Phenotypic variation, which can result from underlying genetic variation or plasticity, is an important metric to understand ...eco‐evolutionary responses to environmental change. Recent work suggests that urban populations might have higher levels of phenotypic variation than non‐urban counterparts. This prediction, however, has never been tested across species nor over a broad geographical range. Here, we conducted a meta‐analysis of the avian literature to compare urban versus non‐urban means and variation in phenology (i.e. lay date) and reproductive effort (i.e. clutch size, number of fledglings). First, we show that urban populations reproduce earlier and have smaller broods than non‐urban conspecifics. Second, we show that urban populations have higher phenotypic variation in laying date than non‐urban populations. This result arises from differences between populations within breeding seasons, conceivably due to higher landscape heterogeneity in urban habitats. These findings reveal a novel effect of urbanisation on animal life histories with potential implications for species adaptation to urban environments (which will require further investigation). The higher variation in phenology in birds subjected to urban disturbance could result from plastic responses to a heterogeneous environment, or from higher genetic variation in phenology, possibly linked to higher evolutionary potential.
Phenotypic variation is an important metric to understand eco‐evolutionary responses to environmental change. We conduct a meta‐analysis of the bird literature to compare urban versus non‐urban means and variation in phenology and reproductive effort. We show that urban populations reproduce earlier, have smaller broods and have higher phenotypic variation in laying date than non‐urban conspecifics.
Desynchrony of phenological responses to climate change is a major concern for ecological communities. Potential uncoupling between one of the most fundamental divisions within populations, males and ...females, has not been well studied. To address this gap, we examined sex-specific plasticity in hibernation phenology in two populations of Columbian ground squirrels (
Urocitellus columbianus
). We find that both sexes display similar phenological plasticity to spring snowmelt dates in their timing of torpor termination and behavioural emergence from hibernation. As a result of this plasticity, the degree of protandry (i.e. males' emergences from hibernation preceding those of females) did not change significantly over the 27-year study. Earlier male behavioural emergence, relative to females, improved the likelihood of securing a breeding territory and increased annual reproductive success. Sexual selection favouring earlier male emergence from hibernation may maintain protandry in this population, but did not contribute to further advances in male phenology. Together, our results provide evidence that the sexes should remain synchronized, at least in response to the weather variation investigated here, and further support the role of sexual selection in the evolution of protandry in sexually reproducing organisms.
Flexible MOF nanoparticles,
i.e.
MOF nanoparticles that change their structure upon external stimuli such as guest uptake, are promising for numerous applications including advanced gas adsorption, ...drug delivery and sensory devices. However, the properties of MOFs are typically characterised based on the bulk material with no consideration of how the particle size and external surface influences their performance. This combined computational and experimental contribution investigates the influence of the particle size and surface functionalisation on the flexibility of DUT-8(Ni) (Ni
2
(2,6-ndc)
2
dabco, ndc = naphthalene dicarboxylate, dabco = 1,4-diazabicyclo2.2.2octane, DUT = Dresden University of Technology). DUT-8 nanoparticles remain rigid in their open pore form while microparticles, synthesised under slightly different conditions, undergo gate opening upon nitrogen adsorption suggesting that the particle size has an important role to play in the flexibility of DUT-8. While the adsorption environment at the surface capped with modulators smaller than the 2,6-ndc ligand is very different compared to the bulk of the crystal with considerably weaker guest-framework interaction, simulations reveal that the nanoparticles should close. We conclude that the size of the nanoparticles is not the major contributor for keeping DUT-8 nanoparticles open but that it is more likely that defects or nucleation barriers dominate. Moreover, our work reveals for the first time that functionalising the external surface of nanoparticles with different modulators or capping groups offers the opportunity to manipulate the gate opening/closing pressure. This principle is generally applicable and could be exploited to tune the gate opening/closing pressure for the application of interest.
Functionalising the external surface of flexible MOF nanoparticles allows manipulating the gate opening/closing pressure.
Background
Youth mental health has declined since the COVID-19 pandemic began. Health coaching and mindfulness-based intervention may support therapeutic processes that promote resilience in the face ...of risk factors for adverse mental health outcomes. Building Resilience for Healthy Kids (HK) is a school-based intervention designed to support mental health through targeting these processes.
Objective
In this study, we tested HK in a pilot randomized controlled trial. Specifically, we examined intervention effects on the theoretically-informed therapeutic processes of emotion regulation, mindfulness, self-efficacy, and resilience and the clinical outcomes of depression and anxiety symptoms. The trial took place between April and June 2021, offering an opportunity to assess the impact of HK in the context of COVID-19.
Methods
Participants were early adolescents (
N
= 230), randomized to HK or assessment-only. Participants in the intervention condition received weekly one-on-one sessions with health coaches. All youth completed validated self-report measures at baseline and post-intervention.
Results
Linear mixed effects models indicated that participants who received HK had a greater reduction in emotion regulation difficulties, relative to assessment-only controls (
d
= 0.84, large effect). Follow-up analyses revealed that youth who endorsed negative affectivity at baseline experienced more benefits than those who did not, and youth who attended more HK sessions increased in self-efficacy, in addition to improved emotion regulation. Intervention effects did not reach significance for other outcomes.
Conclusions
Findings suggest that HK may support youth in reducing difficulties in emotion regulation, which are precursors to the development of mental health concerns in adolescence.
TRN
NCT04202913, 12/16/2019.
PDF
