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Oestridae Causing Myiasis
No full textDue to their habit of feeding on live tissues, larvae of the family Oestridae are known as causative agents of obligatory myases of many animal species, including humans. This group of flies includes a large number of species, about 150, ranked in four sub-families which cause internal organ myases with formation of subcutaneous warbles (Hypodermatinae) or infestations in the digestive tract (Gasterophilinae), nasal or pharyngeal cavities (Oestrinae) or dermis (Cuterebrinae). Oestrids evolved a high degree of host specificity with complex biological life cycles and strict interaction with the host immune system. Oestrids may impair livestock productions through adult fly disturbance of grazing animals (e.g. reduction in weight gain and milk production), or larval direct damage in infested organs (e.g. ulcers in the mouth and nasal cavities or in the digestive tract), allergic reactions and even death of animals in severe cases. Humans may be occasionally infested with skin, ocular and internal organs myases. For some myiases, such as cattle hypodermoses, migrating larvae elicit both cellular and antibody responsiveness in the host and early serological detection of specific antibodies have allowed the validation of diagnostic tools supporting the decision of treating infested animals. Consequently, the systemic use of macrocyclic lactones has greatly reduced the overall burden of these myases, though they still remain a problem in livestock in many parts of the world. In this chapter, we summarize the epidemiology, life cycle, the medical and veterinary importance as well as the control of the main species belonging to the family Oestridae
<b>Estudos morfológicos e investigação da presença de bactérias e protozoários em ácaros (Trombidiformes), parasitos de répteis e anfíbios, no estado de São Paulo</b>
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Chigger Mites (Trombiculidae)
No full texthigger mites are parasitic hexapod larvae belonging mainly to the family Trombiculidae, which cause dermatitis (known as trombiculosis or trombiculiasis) in many animal species, including humans. Species of medical and veterinary importance belong to the genus Eutrombicula Ewing, 1938 in the Neotropics and Neartic, Neotrombicula Hirst, 1925 in the Paleartic and Leptotrombidium Nagayo et al., 1916 in the Oriental region. Species of the genus Leptotrombidium are associated with rodents, potentially acting as vectors of rickettsial disease (i.e., scrub typhus) by Orientia tsutsugamushi in humans. Chigger mites have a worldwide distribution and a low host specificity, being able to infest mostly anthropized environments. Their biological life cycle mainly occurs in the environment (i.e., eggs, prelarvae, quiescent protonymphs, active deutonymphs, quiescent tritonymphs and finally adults), with only larvae as parasitic stage on host. Species that occur in temperate regions can complete up to three generations, whereas tropical ones have continuous cycles all year round. The distribution and diversity of chigger mites is given by the environmental conditions, region and host availability. Their pathogenic effect depends on the parasitic load and on the length of the feeding structure (known as stylostome), which varies according to the species of chigger. Although not truly considered chigger mites, the family Leeuwenhoekiidae has two genera of noticeable veterinary importance (Hannemania and Straelensia). Larvae of Hannemania spp. are intradermic, typically associated with amphibians, while those of the genus Straelensia attach within the inner surface of hair follicles of dogs and Iberian ibex (Capra pyrenaica), forming intradermic solid nodules. Topical repellents are used to prevent and control trombiculiasis by avoiding mite bites. Also, the control of rodent populations is effective as a long-term measure to reduce scrub typhus. For intradermic mites, treatment can be achieved with systemic avermectins, whereas topical acaricides are not useful
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
Reptile vector-borne diseases of zoonotic concern
No full textReptile vector-borne diseases (RVBDs) of zoonotic concern are caused by bacteria, protozoa and viruses transmitted by arthropod vectors, which belong to the subclass Acarina (mites and ticks) and the order Diptera (mosquitoes, sand flies and tsetse flies). The phyletic age of reptiles since their origin in the late Carboniferous, has favored vectors and pathogens to co-evolve through millions of years, bridging to the present host-vector-pathogen interactions. The origin of vector-borne diseases is dated to the early cretaceous with Trypanosomatidae species in extinct sand flies, ancestral of modern protozoan hemoparasites of zoonotic concern (e.g., Leishmania and Trypanosoma) associated to reptiles. Bacterial RVBDs are represented by microorganisms also affecting mammals of the genera Aeromonas, Anaplasma, Borrelia, Coxiella, Ehrlichia and Rickettsia, most of them having reptilian clades. Finally, reptiles may play an important role as reservoirs of arborivuses, given the low host specificity of anthropophilic mosquitoes and sand flies. In this review, vector-borne pathogens of zoonotic concern from reptiles are discussed, as well as the interactions between reptiles, arthropod vectors and the zoonotic pathogens they may transmit
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
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