Frequency-dependent and correlational selection pressures have conflicting consequences for assortative mating in a color-polymorphic lizard, Uta stansburiana

Acknowledgments We would like to thank the numerous undergraduate researchers involved with this project for their invaluable assistance in lizard rearing and data collection. We also thank D. Haisten, A. Runemark, Y. Takahashi, and M. Verzijden for insightful comments on the manuscript. This project was funded by National Science Foundation DEBOS-15973 to A.G.M. and B.R.S.Peer reviewedPublisher PD

Mechanistic and experimental analysis of condition and reproduction in a polymorphic lizard

The importance of genetic and environmental variation in condition in shaping evolutionary trade-offs have recently been subject to much theoretical discussion, but is very difficult to investigate empirically in most field-based systems. We present the results from mechanistic experimental manipulations of reproductive investment and condition in two female colour morphs (orange and yellow) of side-blotched lizards (Uta stansburiana). We investigated the interactions between throat colour morphs, condition, local social environment and female survival using path-analysis. Using follice-ablation experiments, we show that large clutch size has a negative effect on field survival among yellow females, and that this effect is partly mediated by immunosuppressive effects of large clutches. In orange females these effects were less pronounced, and there was a negative survival effect of strong antibody responses. Hence, we experimentally confirmed our previous findings of correlational selection between female morphotype and immunocompetence, an important condition trait. Manipulation of corticosterone revealed multiple (pleiotropic) direct and indirect effects of this hormone on both condition and reproductive traits. We argue that interaction effects (e.g. between local environments and genotypes) could explain a substantial fraction of variation in condition and reproduction in natural populations. Increased attention to such interaction effects and their fitness consequences will provide novel insights in field studies of selection and reproductive allocation

Scale-free memory model for multiagent reinforcement learning. Mean field approximation and rock-paper-scissors dynamics

A continuous time model for multiagent systems governed by reinforcement learning with scale-free memory is developed. The agents are assumed to act independently of one another in optimizing their choice of possible actions via trial-and-error search. To gain awareness about the action value the agents accumulate in their memory the rewards obtained from taking a specific action at each moment of time. The contribution of the rewards in the past to the agent current perception of action value is described by an integral operator with a power-law kernel. Finally a fractional differential equation governing the system dynamics is obtained. The agents are considered to interact with one another implicitly via the reward of one agent depending on the choice of the other agents. The pairwise interaction model is adopted to describe this effect. As a specific example of systems with non-transitive interactions, a two agent and three agent systems of the rock-paper-scissors type are analyzed in detail, including the stability analysis and numerical simulation. Scale-free memory is demonstrated to cause complex dynamics of the systems at hand. In particular, it is shown that there can be simultaneously two modes of the system instability undergoing subcritical and supercritical bifurcation, with the latter one exhibiting anomalous oscillations with the amplitude and period growing with time. Besides, the instability onset via this supercritical mode may be regarded as "altruism self-organization". For the three agent system the instability dynamics is found to be rather irregular and can be composed of alternate fragments of oscillations different in their properties.Comment: 17 pages, 7 figur

Defensive alliances in spatial models of cyclical population interactions

As a generalization of the 3-strategy Rock-Scissors-Paper game dynamics in space, cyclical interaction models of six mutating species are studied on a square lattice, in which each species is supposed to have two dominant, two subordinated and a neutral interacting partner. Depending on their interaction topologies, these systems can be classified into four (isomorphic) groups exhibiting significantly different behaviors as a function of mutation rate. On three out of four cases three (or four) species form defensive alliances which maintain themselves in a self-organizing polydomain structure via cyclic invasions. Varying the mutation rate this mechanism results in an ordering phenomenon analogous to that of magnetic Ising model.Comment: 4 pages, 3 figure

Performance and system flexibility of the CDF Hardware Event Builder

The CDF Hardware Event Builder (1) is a flexible system which is built from a combination of three different 68020-based single width Fastbus modules. The system may contain as few as three boards or as many as fifteen, depending on the specific application. Functionally, the boards receive a command to read out the raw event data from a set of Fastbus based data buffers ( scanners''), reformat data and then write the data to a Level 3 trigger/processing farm which will decide to throw the event away or to write it to tape. The data acquisition system at CDF will utilize two nine board systems which will allow an event rate of up to 35 Hz into the Level 3 trigger. This paper will present detailed performance factors, system and individual board architecture, and possible system configurations

Final clinical practicum, transition experience and turnover intentions among newly graduated nurses: A cross sectional study

BackgroundThe shortage of nurses is a global issue, and turnover rates are especially high for newly graduated nurses. The transition from student to nurse is often described as challenging, and the final clinical practicum before graduation is suggested to be important in preparing graduating students for the transition. However, little is known about the actual relationships between the final clinical practicum, transition and turnover intentions.ObjectivesTo examine whether the final clinical practicum experience is associated with the transition experience and turnover intentions of newly graduated nurses, and whether the transition experience mediates the potential relationship between the practicum and turnover intentions.DesignCross-sectional survey study.SettingsThe study was carried out in Finland (October–December 2018).ParticipantsRegistered nurses graduated within the past two years (n = 712).MethodsA new survey instrument with five subscales was developed for measuring the final clinical practicum experience. Transition experience was measured on four scales that demonstrated the emotional, physical, socio-developmental and intellectual domains of the transition: Psychological distress, sleep quality, role conflict/ambiguity, perception of transition and educational preparation. Turnover intentions from job and profession were asked about with two questions. Structural equation modelling was used to explore the associations between the variables. The models were adjusted for multiple potential confounders.ResultsFinal clinical practicum experience was associated with all domains of the transition experience and turnover intentions. The association between the practicum and turnover intentions was partly mediated by the emotional (psychological distress) and socio-developmental (role conflict and ambiguity) domains of the transition.ConclusionsOur findings provide new evidence about the associations between the specific final clinical practicum dimensions and turnover intentions and the specific mechanisms linking this association. These results highlight the importance of final clinical practicums and suggest targets for improving nurses' transition processes during their first years in practice.</div

Integrating Health and Social Services in Finland: Regional Approaches and Governance Models

Introduction: The study explores regional approaches to integrated care, focusing on regions with regular municipality-based and integrated unified health and social care administration. The aim is to describe a governance approach that supports care integration in the regions. Methods: The study draws on analysis of integrated care governance using an extensive collection of administrative documents (n = 176) on regional health and social services within 20 specialised care authorities. The document data were supplemented with interviews of national health and social system evaluation officers. In our analysis, we used deductive content analysis and identified conceptual approaches of social and health care integration according to elements of integrated care governance. Results: Overall, integrated care governance was relatively well advanced. All regional authorities had established at least some preconditions for integrated governance. The stage of integration varied in the different elements of integrated care governance. The regions with unified integrated administrations enabled the more advanced models of integrated care. Conclusions: Various models for cooperation between regional health and social care authorities have emerged in the regions to identify good integrated care practices. The study suggests that the applied theoretical framework and presented elements of integrated care governance can be used to monitor development of care integration

The associations between the final clinical practicum elements and the transition experience of early career nurses: A cross-sectional study

The final clinical practicum before graduation prepares nursing students for the transition from a student to a nurse, but the essential elements of the final clinical practicum that enhance successful transition are not known. We examined the associations of five elements of the final clinical practicum with four indicators of the transition experience in new nurses. We also tested whether psychosocial work characteristics modified these associations. The study sample comprised 712 Finnish nurses who had graduated within the previous two years before the data collection (response rate: 18%). The data were collected using a questionnaire survey in 2018. The elements of the final clinical practicum included (1) the systematicness of the practicum, (2) teacher involvement, (3) the quality of supervision, (4) preparing for the demands of a nurse's work and (5) being part of a professional team. Our results, based on linear regression analysis, showed that all the elements except the quality of supervision were associated with indicators of the transition experience (beta range: from 0.08 to 0.35). Job demands modified several of these associations. The findings of this study highlight the potential for well-implemented final clinical practicums to promote a smoother transition for new nurses.</p

Mobility promotes and jeopardizes biodiversity in rock-paper-scissors games

Biodiversity is essential to the viability of ecological systems. Species diversity in ecosystems is promoted by cyclic, non-hierarchical interactions among competing populations. Such non-transitive relations lead to an evolution with central features represented by the `rock-paper-scissors' game, where rock crushes scissors, scissors cut paper, and paper wraps rock. In combination with spatial dispersal of static populations, this type of competition results in the stable coexistence of all species and the long-term maintenance of biodiversity. However, population mobility is a central feature of real ecosystems: animals migrate, bacteria run and tumble. Here, we observe a critical influence of mobility on species diversity. When mobility exceeds a certain value, biodiversity is jeopardized and lost. In contrast, below this critical threshold all subpopulations coexist and an entanglement of travelling spiral waves forms in the course of temporal evolution. We establish that this phenomenon is robust, it does not depend on the details of cyclic competition or spatial environment. These findings have important implications for maintenance and evolution of ecological systems and are relevant for the formation and propagation of patterns in excitable media, such as chemical kinetics or epidemic outbreaks.Comment: Final submitted version; the printed version can be found at http://dx.doi.org/10.1038/nature06095 Supplementary movies are available at http://www.theorie.physik.uni-muenchen.de/lsfrey/images_content/movie1.AVI and http://www.theorie.physik.uni-muenchen.de/lsfrey/images_content/movie2.AV

Clutch Frequency Affects the Offspring Size-Number Trade-Off in Lizards

Background: Studies of lizards have shown that offspring size cannot be altered by manipulating clutch size in species with a high clutch frequency. This raises a question of whether clutch frequency has a key role in influencing the offspring sizenumber trade-off in lizards. Methodology/Principal Findings: To test the hypothesis that females reproducing more frequently are less likely to tradeoff offspring size against offspring number, we applied the follicle ablation technique to female Eremias argus (Lacertidae) from Handan (HD) and Gonghe (GH), the two populations that differ in clutch frequency. Follicle ablation resulted in enlargement of egg size in GH females, but not in HD females. GH females switched from producing a larger number of smaller eggs in the first clutch to a smaller number of larger eggs in the second clutch; HD females showed a similar pattern of seasonal shifts in egg size, but kept clutch size constant between the first two clutches. Thus, the egg sizenumber trade-off was evident in GH females, but not in HD females. Conclusions/Significance: As HD females (mean = 3.1 clutches per year) reproduce more frequently than do GH females (mean = 1.6 clutches per year), our data therefore validate the hypothesis tested. Our data also provide an inference that maximization of maternal fitness could be achieved in females by diverting a large enough, rather than a higher-than-usual