1,720,954 research outputs found
Zooplankton community’s responses to coastal ecosystem heterogeneity : a meta-transcriptomics approach
No full textZooplankton plays a crucial role in coastal water ecosystems, serving as a link in energy transfer and facilitating biogeochemical cycling. However, their community structures and responses to environmental perturbations remain understudied, particularly in heterogeneous coastal environments. This thesis presents two comprehensive studies exploring the diversity and physiological responses of zooplankton communities toward environmental heterogeneity in the Hong Kong coastal waters. The first study examined the diversity and assembly processes of zooplankton communities across the eastern and western regions of the Hong Kong coast. A metatranscriptomic approach revealed distinct differences in the diversity and composition of zooplankton, with the eastern sites exhibiting the highest alpha diversity. Key zooplankton genera, including Pocilostomaida, Arguloida, Halocyprida, Notostraca, and Euphausiacea, were identified as important in distinguishing the communities between regions. The community structure was primarily shaped by environmental heterogeneity, with a significant distance-decay relationship observed in the eastern regions, and stochastic processes driving the assembly. The second study investigated the impact of coastal environmental nutrient concentration heterogeneity on zooplankton community physiology. Metatranscriptomic analysis uncovered distinct patterns of differential gene expression associated with nitrogen and amino acid metabolism functions across the different sampling regions. These gene expression patterns corresponded to the observed heterogeneity in dissolved inorganic nitrogen and phosphorus concentrations within the zooplankton's living environment. Validation using a laboratory model organism, Daphnia magna, further supported the identified gene ontology functions. Collectively, these findings provide a comprehensive understanding of the diversity, assembly mechanisms, and environmental responses of zooplankton communities in the highly heterogeneous Hong Kong coastal ecosystem. The results underscore the importance of incorporating gene expression analysis to elucidate the physiological processes and ecological roles of zooplankton in the biogeochemical cycle.</p
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
The metabolic mechanisms underlying zooplankton-derived dissolved organic matter’s chemical properties
No full textDissolved organic matter (DOM), the largest reservoir of organic material in the ocean, plays a crucial role in the global carbon cycle and the microbial loop. While existing studies have documented significant DOM release by zooplankton, the chemodiversity and bioavailability of this DOM, along with the physiological mechanisms influencing these characteristics in heterogeneous coastal water environments, remain inadequately explored. We conducted onboard zooplankton DOM release experiments in heterogeneous estuarine-coastal water systems, followed by molecular characterization of the DOM using Fourier-transform ion cyclotron resonance mass spectrometry. Additionally, we analysed zooplankton metabolic activities through meta-transcriptomics to elucidate the relationship between the chemical properties of the released DOM and the underlying physiological processes of zooplankton. Our findings reveal substantial variations in the molecular diversity of DOM released by zooplankton across heterogeneous environment, notably between estuarine and coastal communities. We found strong correlations between the chemical reactivity of the DOM and clusters of orthologous groups (COGs) genes associated with functions such as carbohydrate metabolism, nucleotide processing, energy production, and coenzyme metabolism. Importantly, the aromaticity index (AI) of the released DOM was closely linked to metabolism-related gene functions, indicating that zooplankton metabolic processes significantly influence DOM bioavailability. This study enhances our understanding of how the organism’s metabolic processes shape the molecular characteristics of DOM they release, highlighting its implications for carbon cycling in the environment
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
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