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Politicians’ Theories of Voting Behavior
No full textWhile political scientists regularly engage in spirited theoretical debates about elections and voting behavior, few have noticed that elected politicians also have theories of elections and voting. Here, we investigate politicians’ positions on eight central theoretical debates in the area of elections and voting behavior and compare politicians’ theories to those held by ordinary citizens. Using data from face-to-face interviews with nearly one thousand politicians in 11 countries, together with corresponding surveys of more than twelve thousand citizens, we show that politicians overwhelmingly hold thin, minimalist, “democratic realist” theories of voting, while citizens’ theories are more optimistic and policy oriented. Politicians’ theoretical tendencies—along with their theoretical misalignment from citizens—are remarkably consistent across countries. These theories are likely to have important consequences for how politicians campaign, communicate with the public, think about public policy, and represent their constituents.publishe
Motivation and Volition in the Course of Action
No full textThe Rubicon model of behavioral phases distinguishes between four phases: weighing, planning, acting, and evaluating. Each phase instigates different mental states which are conducive to successfully completing the tasks each of them requires. This chapter first provides an overview of the previously studied effects of these mental states during the phases of weighing and planning on cognition and behavior. Subsequently, the chapter will discuss intention theory, differentiating between two types of intentions: goal intentions versus implementation intentions. Goal intentions represent states or standards an individual wishes to accomplish, while implementation intentions specify the required steps for the realization of the desired goal. The chapter discusses the processes that are initiated when people set these two kinds of intentions, as well as empirically documented effects on goal striving. The chapter closes with future perspectives for research on motivation and volition throughout the behavioral phases.publishe
Health is wealth and documents are the currency : exploring the role of NGOs in facilitating healthcare access for undocumented migrants in the Netherlands : a qualitative study
No full textpublishe
Effect of repeated sessions of dual-site anodal tDCS on post-exercise performance and subjective recovery in recreationally active females : a randomized controlled trial
No full textBackground:
Previous studies have investigated the effects of transcranial direct current stimulation (tDCS) on performance enhancement, but limited research has examined its impact on post-exercise recovery. This study aimed to assess the effects of three consecutive sessions of dual-site anodal tDCS, targeting the primary motor cortex (M1) and the left dorsolateral prefrontal cortex (L-DLPFC), on both subjective and objective recovery measures in recreationally active females.
Methods:
Twenty-five recreationally active females were randomly assigned to either an anodal tDCS group (n = 13) or a sham group (n = 12). Performance and recovery were assessed at three time points: (1) before tDCS intervention, (2) immediately after a fatigue-inducing time-to-exhaustion test, and (3) following a 24-h recovery period. Participants completed a 3-km cycling time trial (TT) and a Sargent Jump Test (SJT) at each assessment. Additionally, after 24 h of recovery, they completed the Total Quality Recovery (TQR) scale and the Wellbeing Questionnaire (WBQ). Following baseline measurements, participants received their assigned intervention, three consecutive daily stimulation sessions (2 mA, 20 min, targeting + F3/-AF8 and +Cz/-AFz simultaneously), before the fatigue-inducing task.
Results:
Both groups exhibited similar physiological and perceived exertion responses during the fatigue-inducing task (all p > 0.05). While the a-tDCS group showed significant improvements in 3-km TT performance at 24 h post-recovery compared to baseline (p 0.05). However, the tDCS group reported higher TQR scores than the sham group at 24 h (p = 0.046, 95% CI [0.000, 2.000]). No significant between-group differences were observed in explosive performance (SJT) or WBQ scores (all p > 0.05).
Conclusion:
Three sessions of dual-site a-tDCS targeting M1 and L-DLPFC may enhance perceived recovery (TQR) in recreationally active females, but do not significantly influence wellbeing (WBQ) or objective performance recovery measures. The benefit appears to be subjective only, without a measurable performance advantage.
Clinical trial registration:
The trial was registered in the Iranian Clinical Trial Registry (www.irct.behdasht.gov.ir, IRCT ID: IRCT20230925059509N1).publishe
From individuals to populations : Behavioral flexibility in foraging of a wide-ranging species
No full textHow, when, and where animals forage determines individual survival and reproductive
success. Foraging is a context-dependent behavior shaped by the interplay between the
environmental and landscape conditions in which the animal lives, their individual behavior, and
social interactions with others. This is particularly important for central place foragers, which travel
long distances to forage and whose constant interactions at their communally-used sites can
ultimately influence their foraging decisions.
During my PhD, I investigated the foraging behavior of a wide-ranging bat species, the greater
spear-nosed bat (Phyllostomus hastatus), at different levels of social organization, from
individuals to populations. I studied a population on Isla Colón, Panama, due to the reported
intraspecific variation in the species. These bats are omnivorous, feeding on temporally
unpredictable resources during the dry season (e.g., the nectar and pollen of flowering balsa
trees, Ochroma pyramidale) and more ubiquitous resources during the wet season (e.g., fruits
and insects). They form stable groups of unrelated females known to socially forage and defend
resources against other female groups during periods of temporal unpredictability, such as when
balsa trees are flowering. In Panama, both female and male bats were observed commuting
independently across the ocean to forage in areas over 25 km away, contrasting with previously
reported shorter distances (< 10 km) and female social foraging during resource-scarce periods.
Given these striking differences in social foraging behavior, the first chapter of my thesis used a
longitudinal GPS-tracking dataset spanning seven years and three colonies, to investigate how
P. hastatus navigate the landscape across seasons. I found that both female and male bats
commuted long distances to colony-specific foraging areas, exploiting known feeding resources
across years with minimal exploration. Foraging areas were shared within, but not always
between, colonies. These results suggest that these bats use socially learned, colony-level
foraging areas, bypassing other potentially available resources.
To delve deeper into group behavior, my second chapter focused on understanding social
structure and group foraging. I did this by comparing the foraging behavior of Isla Colón bats to a
population in Trinidad population in relation to their resource landscapes. Using GPS tracking
data from two female groups on Isla Colón, I investigated coordination in foraging behavior at
different stages – departure times, return times, commutes, and foraging sites – and examined
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how coordination was linked to their social structure. I found high intraspecific variation between
the two populations. Compared to bats in Trinidad, bats on Isla Colón showed no coordination at
departures or during commutes, exhibited high foraging area overlap, and had less stable female
groups that were easily disturbed. These findings highlight this species' high intraspecific variation
in foraging behavior in relation to the resource landscape, and the potential role of social foraging
in shaping their social structure.
Building on the findings of chapters 1 and 2, my third chapter tested individual consistency in
foraging patterns. Following a similar approach as chapter 2, I examined within-individual and
between-individual variation in departure and return times, commuting paths, and foraging areas
across different seasons in two colonies. I also explored how wind and moonlight intensity –
environmental factors known to influence bat foraging decisions – affected their behavior. This
chapter revealed high within-individual consistency in path and site fidelity across seasons. Bats
showed strong fidelity to specific paths and foraging sites, possibly adjusting their commutes to
wind conditions. However, there was high individual variability in their departure times, with delays
observed when there were strong wind conditions and brighter nights. These results emphasize
the specialized foraging behavior of P. hastatus, highlighting the role of memory in shaping their
decisions and their ability to flexibly adjust foraging timings.
The remarkable flexibility of P. hastatus foraging behavior across its distribution underscores the
importance to further investigate the mechanisms shaping these strategies in response to
different local landscapes and environmental conditions. Furthermore, this study reinforces the
need to examine behavior at multiple scales, accounting for both individual and group-level
behaviors that ultimately influence population-level processes.publishe
Why still Koselleck?
No full textThose seeking to gain a deeper understanding of the complex interrelationship between Reinhart Koselleck's oeuvre and the turbulences of the Age of Extremes would be well advised to consult Stefan-Ludwig Hoffmann's Der Riss in der Zeit: Kosellecks ungeschriebene Historik. Hoffmann shows how “Koselleck's personal experience of the abysmal meaninglessness of history” and his “experiences of time in extremis” formed the starting point for his numerous historiographical endeavors and, ultimately, for his unwritten Historik. Hoffmann provides an accessible interpretation of Koselleck's oeuvre, contextualizes its insights as a reflex of the latter's experience of the abysmal crises of the twentieth century, and invites a series of far-reaching questions that point beyond Koselleck. The significance of Koselleck for contemporary historical thought is founded on his historicization of historicism. Whereas the initial crisis of historicism constituted the point of departure for Koselleck's project, it was before the backdrop of a second crisis of historicism that he historicized historicism, embarked on a search for a theory of the conditions of possible histories, and opened up a horizon for a new historical concept of history and understanding of time.publishe
Engineering oxypurinol-responsive riboswitches based on bacterial xanthine aptamers for gene expression control in mammalian cell culture
No full textRiboswitch-mediated control of gene expression without the interference of potentially immunogenic proteins is a promising approach for the development of tailor-made tools for biological research and the advancement of gene therapies. However, the current selection of applicable ligands for synthetic riboswitches is limited and strategies have mostly relied on de novo selection of aptamers. Here, we show that the bacterial xanthine I riboswitch aptamer recognizes oxypurinol, the active metabolite of the widely prescribed anti-gout drug allopurinol (Zyloprim®). We have characterized the aptamer/oxypurinol interaction and present a crystal structure of the oxypurinol-bound aptamer, revealing a binding mode similar to that of the cognate ligand xanthine. We then constructed artificial oxypurinol-responsive riboswitches that showed functionality in human cells. By optimizing splicing-based oxypurinol riboswitches using three different strategies, transgene expression could be induced by >100-fold. In summary, we have developed recombinant RNA switches enabling on-demand regulation of gene expression in response to an established and safe drug.publishe
