1,721,025 research outputs found
Driving kinetically constrained models into nonequilibrium steady states: Structural and slow transport properties
No full textComplex fluids in shear flow and biased dynamics in crowded environments exhibit counterintuitive features which are difficult to address both at theoretical level and by molecular dynamic simulations. To understand some of these features we study a schematic model of highly viscous liquid, the 2D Kob-Andersen kinetically
constrained model, driven into non-equilibrium steady states by a uniform non-Hamiltonian force. We present a detailed numerical analysis of the microscopic behavior of the model, including transversal and longitudinal spatial correlations and dynamic
heterogeneities. In particular, we show that at high particle density the transition from positive to negative resistance regimes in the current vs field relation can be explained via the emergence of nontrivial structures that intermittently trap the particles and slow
down the dynamics. We relate such spatial structures to the current vs field relation in the different transport regimes
Aspetti veterinari e di sanità pubblica nell’allevamento della tilapia (Oreochromis niloticus) in Kenia.
No full textAquaculture is a zootechnical sector in increasing expansion over the world which could be
strategic for the economic and social advancement of developing countries, including the African continent. The
European BOMOSA Project (Integrating BOMOSA cage fish farming systems in reservoirs, ponds and temporary
water bodies in Eastern Africa) (2006-2009) intended to establish small scale fish farming in marginal water
bodies in East African countries creating rural aquaculture networks with the aim to economically integrate
aquaculture with agriculture. In the framework of the BOMOSA project, a study of veterinary and public health
aspects in tilapia (Oreochromis niloticus) cultured in Bomosa fish farming systems has been carried out. The
activities of the DVM thesis here summarized fall in this field and have been performed from October to
December 2007 in Sagana Fish Farm, the main BOMOSA Kenyan hub. In this period a total of 160 tilapias have
been sampled from 11 farm ponds and subjected to complete parasitological examination. In some cases, infected
tissues were fixed in 10% buffered formalin for histology. Furthermore, in order to study the life cycle of some
helminths recovered in the farmed fish, parasitological analyses were carried out on 72 gastropods owing to
Bulinus and Melanoides genera, and 5 piscivorous birds (2 herons Ardea cinerea, 2 hammerkop Scopus umbretta
and 1 cormoran Phalacrocorax carbo). This survey allowed to identify several protozoan, myxozoan and
metazoan parasites which could be pathogenic to farmed fish and, in some case, to humans. The results of
parasitological exams carried out on gastropods and piscivorous birds confirmed the presence of all the suitable
hosts for a successful completion of the life cycle of several helminths recovered from farmed fish
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
Surface and bulk properties of mineral fibres relevant to toxicity
No full textMany physicochemical properties of fibrous minerals concur - often simultaneously - in determining the fate of a particle within the human body. A complex chain of physicochemical transformations and biological reactions occur when a mineral fibre comes in contact with biological material and occasionally this results in inhaled material being held in an organism for a very long time. During that time, which might last for decades in the case of highly bio-persistentminerals such as amphibole asbestos, the fibre evolves and reacts with the human body, initially with body fluids and immune system cells, and dynamically interacts with its biological surroundings. To understand the molecular mechanisms of interaction, both bulk and surface properties of toxic - and potentially toxic - mineral fibres have to be considered. Far from being an exhaustive compendium of the enormous numbers of works dealing with the toxicological properties of minerals, this chapter is devoted to the discrimination of the bulk and surface - often interrelated - properties that impart toxic potential to fibrous minerals. To allow the establishment of a common background for a multidisciplinary audience, some general considerations of the factors influencing the health effect of mineral fibres aimed at clarifying some key toxicological concepts, including dose, exposure, clearance and molecular mechanisms, are provided in the initial paragraphs. Because asbestos accounts undoubtedly for the vast bulk of toxicological research on minerals, an essential introduction of the key toxicological properties of non-asbestos mineral fibres is also provided. The chapter is divided into two main sections dealing with bulk and surface properties of mineral fibres variously involved in toxicological response. Specifically, fibre morphology, biopersistence and fibre surface properties, including the generation mechanisms of particle-induced reactive oxygen species (ROS), the investigation of surface active sites and the surface modification induced by the biological environment, are reported and discussed with the support of more than 200 bibliographic references
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
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