1,720,984 research outputs found
Recommended from our members
Environmental Variables and Gene Expression Profiles Associated with Cueing Reproductive Events in Cnidarians
No full textCoral reproduction is vital to the persistence of coral reefs. Decades of ecological studies have correlated environmental variables, such as temperature and light, to the timing of reproduction in anthozoan cnidarians, including corals and sea anemones. However, elevated temperatures associated with climate change impair reproductive success and threaten the resilience of coral reefs globally. Empirically evaluating the effect of the key environmental variables temperature and light on the timing of reproduction, at ecological and molecular levels, will further our understanding of the impacts of a changing environment on the future of coral reproductive success. At the transcriptomic level, the signaling pathways and mechanisms involved in transducing environmental cues into molecular signals and coordinating reproductive events is poorly understood. The few studies examining molecular events associated with reproduction have focused on spawning corals: no study has examined these events in a brooding coral.
Cnidarians are both evolutionarily and ecologically significant. As early-diverging basal metazoans, they occupy a key position as the sister-taxon to bilaterians, and are the foundational species of coral reef ecosystems. Therefore, hypothesis-generating studies aiming to characterize both novel and homologous genes involved in coordinating reproductive events can provide a basis for detailing the genetic and physiological mechanisms governing reproduction in ancestral animal systems.
In this work, Chapters 2 and 3 investigate the impacts of elevated temperature on reproductive timing in the coral Pocillopora damicornis and integrate ecological and genomic methods to describe environmental and physiological components of reproductive timing in a brooding coral. My findings reveal that there is plasticity in the timing of reproduction at both an ecological and transcriptomic level, as elevated temperature results in earlier larval release and a disruption of transcriptomic profiles associated with the timing of reproduction. Chapter 4 explores the potential of the sea anemone developmental model, Nematostella vectensis as a reproductive model for corals and examines gene expression patterns associated with light + temperature-induced spawning. I describe smaller transcriptomic changes during reproduction, compared to brooding and spawning corals, and suggest that reproductive priming and post-translational regulation leads to modest transcriptional change. Overall, this work describes the impacts of elevated temperature on reproductive timing in a brooding coral and provides a detailed comparison of the transcriptomic mechanisms associated with light + temperature induced reproduction both in a brooding coral in nature and a laboratory-maintained sea anemone
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Recommended from our members
Effects of an Artificial Lunar Cycle on Reproduction in the sea anemone Aiptasia sp.pdf
Get PDFThe tropical sea anemone, Aiptasia sp., is a model organism within the phylum cnidaria, a group that includes globally threatened corals which are the bio-engineers of coral reefs.
Aiptasia reproduce both sexually, in a process known as spawning, and asexually, mainly through a process known as pedal laceration. During spawning, either visible egg bundles or microscopic sperm are released into the water column. During pedal laceration, small pieces of pedal disc separate from the body column and form new anemones. Many cnidarians, particularly corals, show lunar periodicity in their spawning behavior, by spawning often after a full moon.
In this experiment five individual Aiptasia genotypic strain were subjected to an artificial sunlight (white light) and moonlight (LED light) cycle for one year and anemones were examined regularly to determine the timing and amount of sexual and asexual reproduction. Over the course of one year, pedal laceration counts, oral disc diameter measurements, and the number and length of spawning events were measured. Results concluded that Aiptasia did not reproduce on a monthly basis and showed weak synchrony of spawning events.Keywords: Reproduction, Aiptasi
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
- …
