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Bat Monitoring in North Coast and Cascades Network Summer 2019
Full text linkThe detection of white-nose syndrome (WNS) in King County, WA in 2016 prompted the National Park Service to mobilize region-wide bat monitoring and disease surveillance. One of the goals of the Pacific West Region WNS response plan was to implement acoustic monitoring to determine the distribution of bat species and evaluate changes in distribution as WNS spreads. From May to September 2019, we conducted acoustic monitoring at 61 unique sites at two North Coast and Cascades Network (NCCN) parks, Mount Rainier National Park and North Cascades National Park Service Complex). We report results from one of seven elevational transects, Nisqually to Paradise at Mount Rainier National Park. We detected 8 of 11 species known to western Washington. We also detected more bat calls and
higher species diversity in riparian habitats compared to forest openings
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Does the agricultural fungicide Tebuconazole inhibit the growth of the amphibian chytrid fungus?
Full text linkIn the US, significant research is ongoing regarding the interactions of pesticides with species and processes within wetland ecosystems. For example, the effect of such pollutants on amphibian survival and physiology has been an area of focused research. Negative impacts of pesticides to non-target organisms (e.g. amphibians) have been observed. The effects of the fungal disease to amphibians that are also exposed to pesticides is complex, however the effects of pesticides on the free-living fungal pathogen has received little attention. We hypothesized that Tebuconazole would inhibit the growth of the amphibian chytrid fungus in culture. To test this hypothesis, we measured the growth of the fungus exposed to a high concentration of Tebuconazole (0.02mg/ml) over a 12 day period. We observed a rapid increase in fungal density in the first two days of the experiment, followed by a steady decrease in the density. We conclude that a high concentration (0.02 mg/ml) amphibian chytrid fungus growth appears to be inhibited by Tebuconazole, although exposure time appears to be an important factor in the response
The Wood Preservative Potentials of Valonia, Chestnut, Tara and Sulphited Oak Tannins
No full textThis study investigated antifungal properties of four different tannins as potential environmentally friendly wood preservatives. Scots pine wood samples were impregnated with 3, 5, 10, and 15% valonia, chestnut, tara, and sulphited oak tannins, and then were exposed to brown rot fungi Coniophora puteana and Postia placenta, and white rot fungi Trametes versicolor and Pleurotus ostreatus attack to determine the best tannin type and the optimum concentration level for sufficient decay resistance. Leaching test was conducted in order to evaluate any loss in effectiveness in decay resistance due to possibility of tannin leaching. Tannins were found efficacious in suppressing brown rot fungi attacks when no leaching prior the decay test was used, however, they seemed to be ineffective against white rot fungi attacks. The lowest weight losses were obtained with valonia and chestnut tannins both for brown and white rot fungi probable related with their high ellagic tannin content.</p
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
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Emerging infectious disease in lentic environments : the ecology and biogeography of the amphibian chytrid fungus Batrachochytrium dendrobatidis, with perspectives on water quality, limnology, and chemical contaminants
Full text linkBiodiversity losses in terrestrial, freshwater, and marine systems are accelerating at a global scale and the most threatened vertebrate taxa are those associated with freshwater habitats. The causes of biodiversity losses are often complex and include synergistic effects of natural and human-induced stressors, such as habitat loss and fragmentation, urbanization, invasive species, contaminants, global climate change, and emerging infectious diseases. In the last 35 years, the amphibian extinction rate has been estimated to exceed 105 times the baseline expected rate for all species and in the USA, the number of occupied amphibian sites has been reported to be declining by 3.7% per year. Among the many threats to amphibians, the role of disease in population declines has been recognized increasingly over the last two decades. Numerous amphibian diseases have been identified and attributed to mass mortality events. Chytridiomycosis, the emerging infectious disease caused by the amphibian chytrid fungus, Batrachochytrium dendrobatidis (Bd), is implicated as a causal agent in many recent global amphibian population declines and extinctions.
To understand the pathology and conservation implications of Bd, a greater understanding of its ecology, life history, and distribution in the wild is of paramount importance. Although it has an impact on the persistence of selected amphibian populations around the world, the full scope of the effects of chytridiomycosis on global amphibian population declines are not well understood. Most Bd research efforts have focused on Bd in amphibian hosts per se, with little attention to understand the environmental associations and dynamics of free-living Bd outside of the amphibian host. In particular, information on Bd responses to climatic variation outside of hosts is a research gap. Furthermore, as a microorganism within an aquatic environment, studies are lacking of potential water quality associations, how Bd may interact with other members of their biological communities, and how Bd responses to chemical contaminants found in aquatic environments. My research begins to fill these gaps by studying the basic ecology of free-living Bd in field settings, and investigating factors that may influence its distribution at a landscape scale, occurrence at a regional scale, and detection at a site scale.
Herein, I describe spatial and temporal patterns in the detection and density of free-living Bd in aquatic habitats in two different geographic regions of the United States, Alaska (Chapter 2) and Oregon (Chapter 3). The Alaska work examines Bd ecology at the northernmost extent of amphibian occurrence in North America, where climate associations may be particularly relevant and where Bd occurrence may be representative of one of the most novel pathogen-host systems in the world. I also describe (Chapter 2) experimental results of Bd and amphibian response to extreme cold temperatures they may experience in continental settings, at high elevations, and at high latitudes. My Oregon studies (Chapter 3) focus on multivariate associations of free-living Bd occurrences with a suite of aquatic environmental factors, both abiotic and biotic in nature. In Chapter 4, I describe how amphibians and Bd respond to agricultural chemicals (fungicides) that they may be exposed to in field settings. These results are specific to Bd, but might also warrant consideration as fungicidal treatments for a newly described chytrid affecting salamanders; both of these amphibian chytrids have been detected in captive animals and solutions to treat trade animals for the pathogen are gaining relevancy. Finally, in Chapter 5, I reflect upon the journey of conservation biologists and herpetologists for 25 years of amphibian decline research, with global losses becoming widely recognized in 1989. In this context, my research significantly advances understanding of the geographic distribution and ecology of one potential threat factor to amphibian populations on Earth, Batrachochytrium dendrobatidis. The factors that I report to both promote or limit free-living Bd distribution and abundance will further inform pathogen dynamics research
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