404 research outputs found

    Preinfection in vitro chemotaxis, phagocytosis, oxidative burst, and expression of CD11/CD18 receptors and their predictive capacity on the outcome of mastitis induced in dairy cows with Escherichia coli.

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    Four to 6 wk after parturition, 12 cows in second, fourth, or fifth lactation were experimentally infected in one gland with Escherichia coli. The capacity of chemotaxis, phagocytosis, oxidative burst, and expression of CD11/CD18 receptors to predict the severity of IMI was measured. Bacterial counts in the infected quarter, expressed as area under the curve, and residual milk production in the uninfected quarters were compared to determine severity of the infection. Although these two outcome parameters were highly negatively correlated, regression models with preinfection tests for leukocyte function fitted best with bacterial counts as an outcome parameter. Of the preinfection tests for leukocyte function, chemotaxis best predicted the outcome of the IMI that had been experimentally induced by E. coli. The number of circulating peripheral leukocytes just prior to inoculation was used to predict 52 and 45% of the severity of IMI for bacterial counts and residual milk production, respectively. As a categorical variable, parity predicted 75 and 56% of the severity of IMI expressed as bacterial counts and residual milk production, respectively. Because of the strong effect of parity on the outcome of the experimentally induced mastitis, analysis was performed to discriminate between second parity cows and older cows. Significant differences were found for the number of circulating peripheral leukocytes and for the expression of CD11b/CDl8 and CD11c/CD18 receptors between younger and older cows

    The Quality vs. the Quantity of Schooling: What Drives Economic Growth?

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    This paper challenges Hanushek and Woessmann’s [2008] contention that the quality and not the quantity of schooling determines a nation’s rate of economic growth. I first show that their statistical analysis is flawed. I then show that when a nation’s average test scores and average schooling attainment are included in a national income model, both measures explain income differences, but schooling attainment has greater statistical significance. The high correlation between a nation’s average schooling attainment, cumulative investment in schooling, and average tests scores indicates that average schooling attainment implicitly measures the quality as well as the quantity of schooling

    Release of Lungworm Larvae from Snails in the Environment: Potential for Alternative Transmission Pathways

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    Background: Gastropod-borne parasites may cause debilitating clinical conditions in animals and humans following the consumption of infected intermediate or paratenic hosts. However, the ingestion of fresh vegetables contaminated by snail mucus and/or water has also been proposed as a source of the infection for some zoonotic metastrongyloids (e.g., Angiostrongylus cantonensis). In the meantime, the feline lungworms Aelurostrongylus abstrusus and Troglostrongylus brevior are increasingly spreading among cat populations, along with their gastropod intermediate hosts. The aim of this study was to assess the potential of alternative transmission pathways for A. abstrusus and T. brevior L3 via the mucus of infected Helix aspersa snails and the water where gastropods died. In addition, the histological examination of snail specimens provided information on the larval localization and inflammatory reactions in the intermediate host. Methodology/Principal Findings: Twenty-four specimens of H. aspersa received ~500 L1 of A. abstrusus and T. brevior, and were assigned to six study groups. Snails were subjected to different mechanical and chemical stimuli throughout 20 days in order to elicit the production of mucus. At the end of the study, gastropods were submerged in tap water and the sediment was observed for lungworm larvae for three consecutive days. Finally, snails were artificially digested and recovered larvae were counted and morphologically and molecularly identified. The anatomical localization of A. abstrusus and T. brevior larvae within snail tissues was investigated by histology. L3 were detected in the snail mucus (i.e., 37 A. abstrusus and 19 T. brevior) and in the sediment of submerged specimens (172 A. abstrusus and 39 T. brevior). Following the artificial digestion of H. aspersa snails, a mean number of 127.8 A. abstrusus and 60.3 T. brevior larvae were recovered. The number of snail sections positive for A. abstrusus was higher than those for T. brevior. Conclusions: Results of this study indicate that A. abstrusus and T. brevior infective L3 are shed in the mucus of H. aspersa or in water where infected gastropods had died submerged. Both elimination pathways may represent alternative route(s) of environmental contamination and source of the infection for these nematodes under field conditions and may significantly affect the epidemiology of feline lungworms. Considering that snails may act as intermediate hosts for other metastrongyloid species, the environmental contamination by mucus-released larvae is discussed in a broader context

    Preinfection chemotactic response of blood polymorphonuclear leukocytes to predict severity of Escherichia-coli mastitis.

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    Experimental mastitis was induced by inoculating rear right quarters of 10 healthy cows with 10(3) cfu of Escherichia coli. The chemotactic responses of peripheral blood polymorphonuclear leukocytes at d -6, -5, -2, -1, and immediately prior to inoculation were measured. Chemiluminescence of polymorphonuclear leukocytes was measured immediately prior to inoculation. Severity of the experimental mastitis was assessed by bacterial growth in the inoculated quarters. Results of this study indicated that severity of the experimental mastitis may be predicted by the chemotactic response in vitro of polymorphonuclear leukocytes isolated from the peripheral blood at d 2, d 1, and immediately prior to inoculation. The number of circulating polymorphonuclear leukocytes immediately prior to inoculation also showed a negative relationship with the severity of mastitis. No relationship existed between preinfection chemiluminescence of polymorphonuclear leukocytes and the severity of the experimental mastitis. Preinfection chemotactic response of polymorphonuclear leukocytes and preinfection numbers of circulating polymorphonuclear leukocytes appeared to be valuable as predictors of severity of experimental E. coli mastitis in cows

    "Feed from the Service": Corruption and Coercion in the State-University Relations in Central Eurasia

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    Education in Central Eurasia has become one of the industries, most affected by corruption. Corruption in academia, including bribery, extortions, embezzlement, nepotism, fraud, cheating, and plagiarism, is reflected in the region’s media and addressed in few scholarly works. This paper considers corruption in higher education as a product of interrelations between the government and academia. A substantial block of literature considers excessive corruption as an indicator of a weak state. In contrast to standard interpretations, this paper argues that in non-democratic societies corruption is used on a systematic basis as a mechanism of direct and indirect administrative control over higher education institutions. Informal approval of corrupt activities in exchange for loyalty and compliance with the regime may be used in the countries of Central Eurasia for the purposes of political indoctrination. This paper presents the concept of corruption and coercion in the state-university relations in Central Eurasia and outlines the model which incorporates this concept and the “feed from the service” approach. It presents implications of this model for the state-university relations and the national educational systems in Central Eurasia in general and offers some suggestions on curbing corruption

    La estrategia Educativa 2020 o las limitaciones del Banco Mundial para promover el "aprendizaje para todos"

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    La nueva Estrategia Educativa 2020 del Banco Mundial establece las prioridades de reforma educativa en paises en vias de desarrollo para la decada siguiente. El titulo explicito de la estrategia, Aprendizaje para Todos, es un claro reconocimiento de que, mas alla de politicas centradas en el acceso, se debe hacer algo mas para asegurar que la educacion derive en experiencias positivas de aprendizaje. Sin embargo, como este articulo sostiene, las opciones de politicas explicitas y latentes en la Estrategia 2020 no son las mas adecuadas para lograr el Aprendizaje para Todos. El articulo desarrolla tres tipos de argumentos al respecto. El primero se refiere al fuerte apego del Banco a un conocimiento disciplinario y un enfoque metodológico que es insufi ciente para entender lo que aprenden los niños en la escuela y por que. El segundo argumento se refiere al sesgo pro-mercado de la Estrategia por lo que respecta a la reforma del sector publico y a nuevas formas de oferta educativa. En tercer lugar, el articulo senala las principales ausencias de la Estrategia, con especial atencion a las omisiones relacionadas con la compleja relación entre educación y pobreza.The World Bank's 2020 Education Strategy establishes the new education priorities in developing countries for the next decade. Its title, Learning for All, clearly recognizes that, beyond policies focusing on access, something else must be done to ensure that schooling involves positive learning experiences. However, as this paper argues, the 2020 Strategy explicit and latent policy options might not be adequate to achieve Learning for All. This paper develops three arguments on that matter. The fi rst one refers to the Bank's strong attachment to a disciplinary knowledge and a methodological approach that do not suffi ce to understand what children learn at school and why. The second one addresses its pro-market bias when it approaches the public sector reforms and the new forms of providing education. The last argument points out the main omissions of this Strategy, especially in what regards the complex relation between education and poverty

    School Effects on the Wellbeing of Children and Adolescents

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    Well-being is a multidimensional construct, with psychological, physical and social components. As theoretical basis to help understand this concept and how it relates to school, we propose the Self-Determination Theory, which contends that self-determined motivation and personality integration, growth and well-being are dependent on a healthy balance of three innate psychological needs of autonomy, relatedness and competence. Thus, current indicators involve school effects on children’s well-being, in many diverse modalities which have been explored. Some are described in this chapter, mainly: the importance of peer relationships; the benefits of friendship; the effects of schools in conjunction with some forms of family influence; the school climate in terms of safety and physical ecology; the relevance of the teacher input; the school goal structure and the implementation of cooperative learning. All these parameters have an influence in promoting optimal functioning among children and increasing their well-being by meeting the above mentioned needs. The empirical support for the importance of schools indicates significant small effects, which often translate into important real-life effects as it is admitted at present. The conclusion is that schools do make a difference in children’s peer relationships and well-being
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