1,721,003 research outputs found
Development of an enzyme immunoassay to measure urinary and faecal 5α-androst-16-en-3-one in pigs
No full textAndrostenone, a volatile steroid that possesses pheromonal activity, is responsible for boar taint, sexual interactions, and reproduction in pigs. A wide range of analytical methods has been developed to quantify and detect androstenone in adipose tissue and blood, which are invasive procedures. Therefore, the present study aimed to develop a non-invasive method to detect and quantify the androstenone. We produced group-specific polyclonal androstenone antibody to standardize and validate an enzyme immunoassay to measure faecal and urinary androstenone in Yorkshire boars and sows. Parallelism was performed to determine the immunoreactivity between faecal and urinary immunoreactive androstenone and respective antibody. In boars, urinary and faecal androstenone concentrations were higher on the day of mounting and copulation with sows. In sows, we also measured faecal progesterone metabolites to confirm the oestrus and mating. Faecal androstenone concentrations were peaked on the day of oestrus and mating in sows. Our results suggest that androstenone could be detected and quantified in faecal and urine samples of boars and sows. • Developed an enzyme immunoassay for measuring 5α-androst-16-en-3-one as a marker of boar taint and sex pheromone in urine and faeces of pigs • Detection of 5α-androst-16-en-3-one using a non-invasive metho
Deep sequencing of extracellular eDNA enables total biodiversity assessment of ecosystems
No full textThe global decline in biodiversity driven by anthropogenic factors necessitates biomonitoring of ecosystems. However, current approaches are limited to targeted detection of taxa and fail to capture the total biodiversity of ecosystems. We postulated that extracellular environmental DNA (eDNA) represents a genetic repertoire of all the life forms in an ecosystem, which can be retrieved by deep sequencing. The feasibility and effectiveness of this approach were tested through a spatiotemporal study in Chilika Lagoon, a large and biodiverse Ramsar wetland ecosystem in India. Extracellular eDNA was enriched from large-volume filtered water samples using lysis-free methods and over 10.96 billion extracellular eDNA fragments were sequenced from 16 PCR-free shotgun sequencing libraries. The taxonomic classification results show that organisms from all the domains of life, including the low-abundant non-microbial taxa, can be detected with high sensitivity for taxonomic families with representative genomes. Interestingly, despite Bacteria representing a large proportion (87%) of the taxonomically classified reads, Eukaryotes showed the highest taxonomic diversity (73%). Further, using incidence-based asymptotic richness analysis, the total taxonomic diversity of Chilika was estimated to be 1071 families across the tree of life, comprising approximately 799 families of Eukaryotes, 230 families of Bacteria, 27 families of Archaea, and 13 families of DNA Viruses. We also quantified the compositional changes using Bray-Curtis dissimilarity and showed that extracellular eDNA can resolve the broad-scale spatiotemporal variation of biodiversity across the tree of life. These results demonstrate that PCR-free deep sequencing of extracellular eDNA is an effective approach for taxonomic diversity assessment across the tree of life in large ecosystems. With the increasing genomic resources and decreasing sequencing costs, we foresee its widespread application to monitor future biodiversity loss and support conservation, restoration, and management efforts in the Anthropocene
Glucocorticoid concentration and parasitic load in a wild striped hyaena (Hyaena hyaena) population in Southern India
No full textGlucocorticoid levels (GCs) are an important parameter that infers the pathological condition of an organism. GCs can vary with life history stages like gender, age, and reproductive stage and signify the degree of allostatic load experienced. Deleterious increases in GCs can severely affect the wildlife population by suppressing the reproductive viability of individuals and may cause immunosuppressive, making the population more susceptible to parasitic load. We have studied the stress physiology and parasitic load across the life history stages in the striped hyaena population confined to the Moyar Valley of Mudumalai and Sathyamangalam Tiger Reserves. The fecal glucocorticoid metabolite concentrations were measured using cortisol enzyme immunoassay from 30 scats. Collected scats were categorized into adults, sub-adults, and juvenile age groups based on the size and colour of droppings. Sex of the scat samples was identified post-DNA extraction from their epithelial lining cells. Parasitic load from scats was quantified as the number of different parasites recorded through sucrose floatation and sedimentation techniques. We found no significant difference in GCs concentration and parasitic load across the life history stages, but juveniles were recorded to have the least parasitic load. The highest GCs concentration and parasitic load were recorded from adults and female individuals, while both parameters were found least among juvenile individuals. Though we did not observe any significant differences across life-history stages, this study provides the first baseline information on stress physiology and parasitic load in striped hyaenas, which could help further studies assess the impact of external perturbations on stress physiology.K. Ashish, B. Arora, Divyasree Karne, Vinod Kumar, Aamer Sohel Khan, Govindhaswamy Umapathy, T. Ramesh, Riddhika Kall
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
Impact of Habitat Fragmentation on the Demography of Lion-tailed Macaque (Macaca silenus) Populations in the Rainforests of Anamalai Hills, Western Ghats, India
No full textDispelling 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
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