1,720,974 research outputs found
Projected effect of global change on species' change in extinction risk
Full text linkClimate change has become one of the major drivers of biodiversity loss, its effects are not only already evident across all levels of biological organization (from genes to ecosystems) but are projected to increase in the coming decades. The probability of a species or population being negatively impacted by climate change (i.e., risk) is determined by the occurrence of adverse climatic events or trends (i.e., hazard), the occurrence of the species or population in areas that could be impacted (i.e., exposure), and their predisposition to be adversely affected, including their sensitivity or susceptibility and lack of capacity to cope or adapt (i.e., vulnerability). Species or populations can adapt to adverse climatic conditions by shifting their geographical distribution or adapting in situ, generally by changing their phenology, morphology or physiology.
Recent efforts to assess the impacts of climate change have predominantly relied on bioclimatic niche modeling, which predicts species’ or populations’ distributions by linking their geographical range and bioclimatic variables. However, these models assume that all species are affected and will respond to climate change similarly, and do not consider differences in vulnerability and exposure. Trait-based assessments have aimed to address this gap, identifying which traits influence risk, allowing assessing multiple species simultaneously in a simple way and serving as a useful tool for prioritizing conservation actions, especially in the absence of distribution data. However, their applicability can be limited as they are not spatially explicit, the relationship between traits and responses is still uncertain, there are gaps in trait data availability and the approach is generally implemented at the species level, ignoring intraspecific differences in exposure, vulnerability and hazard. The objective of this thesis is to overcome some of these limitations for birds and terrestrial non-volant mammals.
To overcome gaps in mammal trait data availability, I compiled in my first chapter COMBINE: A Coalesced Mammal Database of Intrinsic and Extrinsic traits data for 54 traits for 6,234 mammal species, using data from 14 different data sources. These traits covered aspects such as physiology, reproduction, behavior, longevity, diet, and dispersal. I further filled in gaps in the data through a phylogenetic multiple imputation procedure, providing a complete dataset for 21 traits. All data sources and imputed data were flagged, facilitating identifying the origin of the data. This dataset constitutes a useful tool for large-scale ecological and conservation analyses that use traits, including identifying species at risk from climate change. In my second analytical chapter, Relative latitude, temperature increase and breadth of climatic niche influence mammal populations’ response to climate change, I identified current terrestrial non-volant mammal responses to climate change and the intrinsic traits and environmental factors influencing risk. To achieve this, I first performed a literature review on responses to climate change and categorized them into changes in (a) distribution and abundance, (b) phenology, and (c) morphology. I also identified the direction of each type of response: expansion or contraction for distribution and abundance, advance or delay for phenology, increase or decrease for body size, and no change if no response was detected. To model the relationship between risk from climate change and intrinsic and environmental factors, I focused exclusively on distribution and abundance responses due to their direct relationship. I then selected and obtained data for a series of intrinsic traits and environmental factors previously associated with climate change risk. To account for intraspecific variability in environmental factors, I identified populations of the species that experience similar climatic conditions. As these populations were distributed across large geographical areas, I grouped the responses by species and country, reducing the number of instances of opposing or mixed responses (i.e., different studies for the same species and country reporting distribution and abundance contractions and expansions or phenological advances and delays) and allowing the inclusion of the location of the response within the population. I obtained 382 responses belonging to 130 species located in 30 countries. Most of these responses were distribution and abundance responses (80.6%) while phenological and morphological changes constituted 4.5% (17 responses) and 10.2% (39 responses) respectively. The remaining 4.7% did not fit into any of these categories. Regarding distribution and abundance responses, there were more than twice as many contractions (46.43%) as expansions (20.78%), while in 32.79% of cases there was no clear response. The results of our model indicated that contractions were more likely at the warm edge of the population, while expansions were more likely at the cold edge. Small litter size, hibernation, high temperature increase, low climate seasonality and low altitudinal breadth were also linked to an elevated risk of experiencing a negative response.
In my third analytical chapter, Local environmental factors influence bird distribution and phenological responses to climate change, I followed the same approach but focused on bird distribution and abundance and spring phenological responses to climate change. I also gathered data for nine intrinsic bird traits that have been previously hypothesized to be relevant in determining responses to climate change. This allowed me to identify which intrinsic traits and environmental factors influence experiencing distribution contractions or expansions and spring phenological advances, delays or no changes. I obtained 3,012 responses for 918 species located in 32 countries, 60% of them were distribution and abundance responses and the remaining 40% were spring phenology responses. I found that environmental factors played an important role in determining both distribution and abundance and phenological responses to climate change. Maximum temperature, restricted climate seasonality, relative latitudinal position, and maximum longevity influenced the probability of experiencing contractions and a subsequent increase in risk. Similarly, maximum temperature, climate seasonality, relative latitudinal position, and temperature increase influenced the probability of experiencing advances in spring phenology.
The results presented in this thesis constitute an advance in current knowledge on the variables influencing responses to climate change locally and serve as a starting point for future research
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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