328 research outputs found

    Explaining Species Diversity By Linking Local and Large Scale Processes

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    Large-scale processes are known to be important for patterns of species richness, yet the ways in which local and larger scale processes interact is not clear. I first examined published experiments that manipulated dispersal among local communities using meta- analyses. I show that local communities often readily increase diversity, but that there may be declines at larger spatial scales. I then used metacommunities consisting of microbial aquatic communities to examine how processes at different scales affect local and metacommunity richness. Specifically, I manipulated the potential dispersal rate, whether dispersal was localized or global, and variation in initial community composition. I showed that a low dispersal rate and intermediate distance dispersal enhanced local richness. Initial assembly variation had no effect on local richness, while a lack of dispersal or global dispersal reduced local richness. I also show that predation undoes any diversity increases associated with dispersal. At the metacommunity scale, richness was enhanced throughout the time course of the experiment by initial compositional variation and was reduced by high or global dispersal. Also predation identically structured local communities, and thus reveals large impacts at the metacommunity scale. I further show that these organisms exhibit competition- colonization tradeoffs, and examine how local scale disturbances can structure species diversity. If species are evenly distributed along this tradeoff, then diversity is maximized at intermediate disturbance rates. However if the tradeoff is colonist-skewed then diversity increases with disturbance, and declines is the tradeoff is competitor-skewed. But patterns of diversity at scales larger than the local community always show that diversity is maximized at intermediate disturbances, regardless of the distribution of species along the competition-colonization tradeoff. These results indicate that the effects of dispersal on species richness have a complex relationship with scale and are not solely divisible in to regional versus local scales. Finally, predictions of how dispersal structures communities appear dependent on local-scale processes, species interactions and historical assembly and disturbance frequency

    Phylogenetic diversity promotes ecosystem stability

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    Ecosystem stability in variable environments depends on the diversity of form and function of the constituent species. Species phenotypes and ecologies are the product of evolution, and the evolutionary history represented by co-occurring species has been shown to be an important predictor of ecosystem function. If phylogenetic distance is a surrogate for ecological differences, then greater evolutionary diversity should buffer ecosystems against environmental variation and result in greater ecosystem stability. We calculated both abundance-weighted and unweighted phylogenetic measures of plant community diversity for a long-term biodiversity–ecosystem function experiment at Cedar Creek, Minnesota, USA. We calculated a detrended measure of stability in aboveground biomass production in experimental plots and showed that phylogenetic relatedness explained variation in stability. Our results indicate that communities where species are evenly and distantly related to one another are more stable compared to communities where phylogenetic relationships are more clumped. This result could be explained by a phylogenetic sampling effect, where some lineages show greater stability in productivity compared to other lineages, and greater evolutionary distances reduce the chance of sampling only unstable groups. However, we failed to find evidence for similar stabilities among closely related species. Alternatively, we found evidence that plot biomass variance declined with increasing phylogenetic distances, and greater evolutionary distances may represent species that are ecologically different (phylogenetic complementarity). Accounting for evolutionary relationships can reveal how diversity in form and function may affect stability

    Plant community responses to habitat fragmentation and anthropogenic degradation in the littoral forests of southeastern Madagascar.

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    Conversion of intact forest into smaller, isolated fragments results in a number of profound and quantifiable changes. The purpose of this research was to examine the effects of fragmentation and to understand better how Malagasy forest structure and composition is affected by landscape-level factors. A total of 3476 trees representing 169 species in 55 families were recorded in 50 x 50 m plots, and 10,282 understory stems representing 195 species in 54 families were found in 10 x 10 m plots. Fragments differed significantly in both tree and understory stem density, species richness and diversity values, and family richness values. Patch- and landscape-level features were used to examine the patterns of density and diversity, and included: fragment size, fragment perimeter-area index, internal perimeter created by roads and trails in each fragment, and the number of villages (as an indicator of human population pressure) per hectare of forest in three expanding radii of 5, 7.5, and 10 km. (Abstract shortened by UMI.)Dept. of Biological Sciences. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2001 .C35. Source: Masters Abstracts International, Volume: 40-06, page: 1461. Adviser: Jon Lovett-Doust. Thesis (M.Sc.)--University of Windsor (Canada), 2001

    Scoring methods in script concordance tests : an exploratory psychometric study

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    BACKGROUND:Despite the increasingly popular role of script concordance test (SCT) scoring methods in the evaluation of clinical reasoning, studies examining these methods in nursing are relatively scarce. This study explored the psychometric properties of five SCT scoring methods. METHOD:An SCT was administered to 12 experts and 43 learners. Scores were calculated using five methods and descriptive statistics. Differences in scores were assessed with the Mann-Whitney U test, and Spearman correlation coefficients were calculated for the different methods. RESULTS:The median scores of both experts and learners differed substantially according to the scoring method used. Learners' scores were statistically different from experts' scores (p < .01) for each method. Spearman coefficients (range, 0.44 to 0.95) were positive for the different methods. CONCLUSION:Further research is needed to refine the influence of SCT scoring methods for use in certifying assessment of clinical reasoning in nursing. [J Nurs Educ. 2023;62(10):549–555.

    Effect of simulation-based education on the preparedness of healthcare professionals for the COVID-19 pandemic : a systematic review and meta-analysis

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    Healthcare organizations around the world have embraced simulation to prepare healthcare professionals to the COVID-19 pandemic. However, this pandemic implies additional educational challenges in rapidly designing simulation activities, while remaining compliant with health and safety measures to prevent the spread of the virus. The effect of simulation-based education in this context remains to be evaluated. Objective: The purpose of this systematic review was to describe the features and evaluate the effect of simulation activities on the preparedness of healthcare professionals and students to safely deliver care during the COVID-19 pandemic. Methods: Databases were searched up to November 2020 using index terms and keywords related to healthcare professions, simulation, and COVID-19. All learning outcomes were considered according to the Kirkpatrick model adapted by Barr et al. (2020). Reference selection, data extraction, and quality assessment were performed in pairs and independently. Results were synthesized using meta-analytical methods and narrative summaries. Results: 22 studies were included, 21 of which were single-group studies and 14 of those included pretest/posttest assessments. Simulation activities were mostly implemented in clinical settings using manikins for training on the use of personal protective equipment, hand hygiene, identification and management of COVID-19 patients, and work processes and patient flow. Large improvements in learning outcomes after simulation activities were reported in all studies. Discussion and conclusion: Results should be interpreted cautiously due to significant threats to the internal validity of studies and the absence of control groups. However, these findings are coherent with the overall evidence on the positive effect of simulation-based education. Future studies should include control groups if feasible.Les organisations de santé ont adopté la simulation pour préparer les professionnels à la pandémie de COVID-19. La conception en accéléré de simulations tout en respectant les mesures de prévention de la propagation du virus amène des défis. Dans ces conditions, l’efficacité de la simulation reste à être évaluée. Objectif : Décrire les caractéristiques et évaluer l’effet de simulations sur la préparation des professionnels de la santé et des étudiants pour fournir des soins sécuritaires pendant cette pandémie. Méthodes : Les bases de données ont été consultées jusqu’en novembre 2020 en utilisant des descripteurs et des mots-clés relatifs aux professions de la santé, à la simulation et à la COVID-19. Tous les résultats d’apprentissage ont été considérés. La sélection des articles, l’extraction des données et l’évaluation de la qualité ont été effectuées par paires. Les résultats ont été synthétisés par des méthodes méta-analytiques et des résumés narratifs. Résultats : 22 études ont été incluses ; 21 à groupe unique et, parmi ces 21, 14 évaluations pré-posttest. Les simulations ont principalement été déployées en milieux cliniques avec des mannequins pour la formation à l’utilisation d’équipements de protection individuelle, au lavage de mains, à l’identification et la prise en charge de patients atteints de la COVID-19 et à l’implantation de procédés organisationnels. Toutes les études rapportent des apprentissages importants après les simulations. Discussion et conclusion : Malgré les limites de validité interne et l’absence de groupes de contrôle, ces résultats sont cohérents avec l’état des connaissances sur les effets positifs de la simulation. De futures études devraient inclure des groupes de contrôle si possible

    Health science communication strategies used by researchers with the public in the digital and social media ecosystem : a systematic scoping review protocol

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    Introduction The optimisation of health science communication (HSC) between researchers and the public is crucial. In the last decade, the rise of the digital and social media ecosystem allowed for the disintermediation of HSC. Disintermediation refers to the public’s direct access to information from researchers about health science-related topics through the digital and social media ecosystem, a process that would otherwise require a human mediator, such as a journalist. Therefore, the primary aim of this scoping review is to describe the nature and the extent of the literature regarding HSC strategies involving disintermediation used by researchers with the public in the digital and social media ecosystem. The secondary aim is to describe the HSC strategies used by researchers, and the communication channels associated with these strategies. Methods and analysis We will conduct a scoping review based on the Joanna Briggs Institute’s methodology and perform a systematic search of six bibliographical databases (CINAHL, EMBASE, IBSS, PubMed, Sociological Abstracts and Web of Science), four trial registries and relevant sources of grey literature. Relevant journals and reference lists of included records will be hand-searched. Data will be managed using the EndNote software and the Rayyan web application. Two review team members will perform independently the screening process as well as the full-text assessment of included records. Descriptive data will be synthesised in a tabular format. Data regarding the nature and the extent of the literature, the HSC strategies and the associated communication channels will be presented narratively. Ethics and dissemination This review does not require institutional review board approval as we will use only collected and published data. Results will allow the mapping of the literature about HSC between researchers and the public in the digital and social media ecosystem, and will be published in a peer-reviewed journal

    Recasting spatial food web ecology as an ecosystem science

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    Background/questions/methods&#xd;&#xa;&#xd;&#xa;Food webs are complex systems in which organisms interact with each other and with the abiotic aspects of their environment, thus acting as the conduit for transfers of energy and nutrients through ecosystems. Classical approaches to food webs focus strongly on patterns and processes occurring at the community level rather than at the broader ecosystem scale. Recent developments in community ecology suggest that spatial processes may be important in affecting food web dynamics and affect ecosystems as well, thus leading to the idea of meta-ecosystems. Here, we make a synthesis on how the links between food web dynamics and spatial ecosystem dynamics may be studied through (i) identifying differences between metacommunity and landscape ecology approaches when dealing with food webs, (ii) arguing that a tighter synthesis of the two approaches is needed for a good understanding of how diversity, ecosystem process and trait distributions in landscapes are related, and (iii) laying out how this gap can be efficiently bridged under the framework of meta-ecosystems.&#xd;&#xa;&#xd;&#xa;Results/conclusions&#xd;&#xa;&#xd;&#xa;We identify two possible sets of processes that drive spatial food webs and the ecosystems they occur in: trait-dependent processes and material-dependent processes. Both of these have been shown to be important in affecting various aspects of food web ecology and we ask how they may compare to each other and how they may interact. We argue that interactions between them, while complex, are likely and depend strongly on the size of the meta-ecosystem and its connectivity. A more integrative framework to the study of spatial food webs, which takes into account both approaches, might be key in better understanding the links between ecosystem and community dynamics at large spatial scales.&#xd;&#xa

    Assessing and addressing sexual concerns in individuals diagnosed with coronary artery disease

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    Background/Aims Sexual concerns are frequently reported in people diagnosed with coronary artery disease. These concerns may be related to disorders in one or more phases of the sexual response cycle (i.e. desire, arousal and orgasm). Sexual concerns have been linked to anxiety, depressive symptoms and feelings of despair. As such, nurses should have an understanding of the aetiology of sexual concerns in this population and use appropriate assessment and support strategies. Methods This clinical article discusses several key aspects of evidence-based practice to assess and address sexual concerns in people diagnosed with coronary artery disease. Findings Early assessment of biological, psychological and pharmacological causes of sexual concerns should be carried out. Sexual counselling may be offered to meet specific information needs. Adding pharmacological agents and referring to a sex therapist can be considered to effectively address the sexual concerns of people within this population. Conclusions Approaches to sexual assessment, main information needs of patients with coronary artery disease regarding their sexual health, and support strategies are presented

    Effect of simulation on cognitive load in health care professionals and students : protocol for a systematic review and meta-analysis

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    Objective: The objective of this review is to assess the effect of simulation activities and their design features on cognitive load in health care professionals and students. Introduction: Simulation activities are now widely implemented in health care professionals’ education. However, the mechanisms by which simulations and their design features lead to health care professionals’ and students’ learning remains unclear. Still, because of their high interactivity and complexity, simulation activities have the potential to impact the cognitive load of learners. Synthesizing evidence regarding this phenomenon could help simulation educators identify the design features that affect learners’ cognitive load, and explain why some simulation activities are more effective than others. Inclusion criteria: This review will consider experimental and quasi-experimental studies in which the effect of a simulation activity on cognitive load in health care professionals or students from any discipline or level of practice is evaluated. All academic and health settings will be included. Methods: Following the guidelines of the JBI methods for systematic reviews of effectiveness, CINAHL, Embase, ERIC, MEDLINE, PsycINFO, and Web of Science will be searched for studies published in English or French, without a date limit. Retrieved studies will be independently screened for inclusion, then critically appraised for methodological quality by two reviewers using standardized JBI tools. Data extraction will be done independently using adapted tools from JBI. Where possible, data will be pooled using meta-analytical methods

    Methodological reporting in feasibility studies : a descriptive review of the nursing intervention research literature

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    Background In reaction to weaknesses in feasibility studies reporting, the Consolidated Standards of Reporting Trials (CONSORT) statement published an extension for feasibility studies in 2016. Aim The aim of this study was to systematically review and appraise the reporting of feasibility studies in the nursing intervention research literature based on the CONSORT statement extension for feasibility studies. Method Papers published prior to January 2018 that described feasibility studies of nursing interventions were retrieved. Components of feasibility studies were coded, and code frequencies were analysed. Results The review included 186 papers. Although most papers (n = 142, 76.3%) included the label ‘pilot’ or ‘feasibility’ in their title, reporting for other components generally did not adhere to one or several CONSORT recommendations. Most papers reported objectives (n = 116, 62.4%), designs (n = 95, 51%), or rationales for sample size (n = 165, 88.7%) that were incongruent with the purpose of feasibility studies. Discussion This review results in two main implications for nursing research. First, we noted that the reporting of feasibility studies is weak. While all papers described feasibility studies, almost half focused exclusively on testing the effectiveness of an intervention. Second, we identified rationales for sample size along with key references that could offer guidance in reporting feasibility studies while being coherent with the CONSORT recommendations
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