1,721,050 research outputs found

    The resilience of coastal ecosystems: A functional trait‐based perspective

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    Coastal ecosystems provide important services to human population, such as nurseries for fish, carbon storage and coastal protection. However, the pressure faced by these systems due to global changes will strongly challenge the capacity of coastal ecosystems to persist. Therefore, it is crucial to understand the resilience of coastal ecosystems.Here, I propose that combining a resilience framework based on ecosystem properties with the functional trait response–effect framework would allow researchers and managers to quantify the resilience of coastal ecosystems. I place emphasis on salt marsh and sand dunes because of the higher availability of studies for these systems.First, I introduce the resilience framework based on ecosystem properties and, second, I show how adopting a functional trait perspective in this framework would allow researchers to link how environmental changes influence ecosystem properties. In turn, measuring the changes in ecosystem properties would allow researchers to measure the resilience of the system.Synthesis. I reviewed several types of disturbances (e.g. storms and sea-level rise) that are threatening the persistence of coastal ecosystems, with an emphasis on salt marshes and sand dunes. Applying this resilience framework reveals, for instance, that the same suite of traits (e.g. plant density and stiffness) increase marsh resistance to multiple threats (e.g. storms and sea-level rise); yet, these traits vary along environmental gradients (e.g. along estuaries) and, therefore, the resilience of marshes vary accordingly. Overall, this framework would allow researchers to gather crucial insights on the resilience of coastal ecosystems and to set reference marks for measuring their resilience under environmental changes

    The First- and Second-Order Ethical Reasons Approach: The Case of Human Challenge Trials

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    At the height of the Covid pandemic, there was much discussion in the literature about using human challenge trials (HCTs) to expedite the development of effective Covid-19 vaccines. Historically, reluctance to fully accept HCTs has largely been due to potential conflicts with the principle of nonmaleficence in bioethics. Only a few commentators have explored this topic in depth. In this paper, we claim that to address ethical concerns regarding HCTs, two types of ethical reasons should be identified and investigated: first-order reasons that can be given to claim that a practice in itself is in direct conflict with the principles of bioethics; and second-order reasons that take into consideration how a practice is carried out and its consequences. We argue that understanding these ethical reasons is crucial for guiding the implementation of HCTs. We investigate a first-order reason against HCTs when the practice is in conflict with the principle of nonmaleficence, and when it is not. Following this argument and assuming there is no first-order reason based on nonmaleficence that hinders using HCTs, we argue there may be second-order reasons to guide implementation of this practice, such as difficulty in obtaining informed consent; protection of the weaker party; and trust in the scientific enterprise

    Below-ground biomass of plants, with a key contribution of buried shoots, increases foredune resistance to wave swash

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    • Background and aims Sand dunes reduce the impact of storms on shorelines and human infrastructure. The ability of these ecosystems to provide sustained coastal protection under persistent wave attack depends on their resistance to erosion. Although flume experiments show that roots of perennial plants contribute to foredune stabilization, the role of other plant organs, and of annual species, remains poorly studied. Furthermore, it remains unknown if restored foredunes provide the same level of erosion resistance as natural foredunes. We investigated the capacity of three widespread pioneer foredune species (the perennial Ammophila arenaria and the annuals Cakile maritima and Salsola kali) to resist dune erosion, and compared the erosion resistance of Ammophila at natural and restored sites. • Methods Cores collected in the field were tested in a flume that simulated a wave swash. A multi-model inference approach was used to disentangle the contributions of different below-ground compartments (i.e. roots, rhizomes, buried shoots) to erosion resistance. • Key Results All three species reduced erosion, with Ammophila having the strongest effect (36 % erosion reduction versus unvegetated cores). Total below-ground biomass (roots, rhizomes and shoots), rather than any single compartment, most parsimoniously explained erosion resistance. Further analysis revealed that buried shoots had the clearest individual contribution. Despite similar levels of total below-ground biomass, coarser sediment reduced erosion resistance of Ammophila cores from the restored site relative to the natural site. • Conclusions The total below-ground biomass of both annual and perennial plants, including roots, rhizomes and buried shoots, reduced dune erosion under a swash regime. Notably, we show that (1) annual pioneer species offer erosion protection, (2) buried shoots are an important plant component in driving sediment stabilization, and (3) management must consider both biological (plants and their traits) and physical (grain size) factors when integrating dunes into schemes for coastal protection

    Deciding the Criteria Is Not Enough: Moral Issues to Consider for a Fair Allocation of Scarce ICU Resources

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    During the first wave of the COVID-19 pandemic in Italy, practitioners had to make tragic decisions regarding the allocation of scarce resources in the ICU. The Italian debate has paid a lot of attention to identifying the specific regulatory criteria for the allocation of resources in the ICU; in this paper, however, we argue that deciding such criteria is not enough for the implementation of fair and transparent allocative decisions. In this respect, we discuss three ethical issues: (a) in the Italian context, the treating physician, rather than a separate committee, was generally the one responsible for the allocation decision; (b) although many allocative guidelines have supported moral equivalence between withholding and withdrawing treatments, some health professionals have continued to consider it a morally problematic aspect; and (c) the health workers who have had to make the aforementioned decisions or even only worked in ICU during the pandemic often experienced moral distress. We conclude by arguing that, even if these problems are not directly related to the above-mentioned issues of distributive justice, they can nevertheless directly affect the quality and ethics of the implementation of allocative criteria, regardless of those chosen

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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