1,355 research outputs found

    Measuring Progress on the Control of Porcine Reproductive and Respiratory Syndrome (PRRS) at a Regional Level: The Minnesota N212 Regional Control Project (Rcp) as a Working Example.

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    Due to the highly transmissible nature of porcine reproductive and respiratory syndrome (PRRS), implementation of regional programs to control the disease may be critical. Because PRRS is not reported in the US, numerous voluntary regional control projects (RCPs) have been established. However, the effect of RCPs on PRRS control has not been assessed yet. This study aims to quantify the extent to which RCPs contribute to PRRS control by proposing a methodological framework to evaluate the progress of RCPs. Information collected between July 2012 and June 2015 from the Minnesota Voluntary Regional PRRS Elimination Project (RCP-N212) was used. Demography of premises (e.g. composition of farms with sows = SS and without sows = NSS) was assessed by a repeated analysis of variance. By using general linear mixed-effects models, active participation of farms enrolled in the RCP-N212, defined as the decision to share (or not to share) PRRS status, was evaluated and used as a predictor, along with other variables, to assess the PRRS trend over time. Additionally, spatial and temporal patterns of farmers' participation and the disease dynamics were investigated. The number of farms enrolled in RCP-N212 and its geographical coverage increased, but the proportion of SS and NSS did not vary significantly over time. A significant increasing (p<0.001) trend in farmers' decision to share PRRS status was observed, but with NSS producers less willing to report and a large variability between counties. The incidence of PRRS significantly (p<0.001) decreased, showing a negative correlation between degree of participation and occurrence of PRRS (p<0.001) and a positive correlation with farm density at the county level (p = 0.02). Despite a noted decrease in PRRS, significant spatio-temporal patterns of incidence of the disease over 3-weeks and 3-kms during the entire study period were identified. This study established a systematic approach to quantify the effect of RCPs on PRRS control. Despite an increase in number of farms enrolled in the RCP-N212, active participation is not ensured. By evaluating the effect of participation on the occurrence of PRRS, the value of sharing information among producers may be demonstrated, in turn justifying the existence of RCPs

    Using Machine Learning to Predict Swine Movements within a Regional Program to Improve Control of Infectious Diseases in the US.

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    Between-farm animal movement is one of the most important factors influencing the spread of infectious diseases in food animals, including in the US swine industry. Understanding the structural network of contacts in a food animal industry is prerequisite to planning for efficient production strategies and for effective disease control measures. Unfortunately, data regarding between-farm animal movements in the US are not systematically collected and thus, such information is often unavailable. In this paper, we develop a procedure to replicate the structure of a network, making use of partial data available, and subsequently use the model developed to predict animal movements among sites in 34 Minnesota counties. First, we summarized two networks of swine producing facilities in Minnesota, then we used a machine learning technique referred to as random forest, an ensemble of independent classification trees, to estimate the probability of pig movements between farms and/or markets sites located in two counties in Minnesota. The model was calibrated and tested by comparing predicted data and observed data in those two counties for which data were available. Finally, the model was used to predict animal movements in sites located across 34 Minnesota counties. Variables that were important in predicting pig movements included between-site distance, ownership, and production type of the sending and receiving farms and/or markets. Using a weighted-kernel approach to describe spatial variation in the centrality measures of the predicted network, we showed that the south-central region of the study area exhibited high aggregation of predicted pig movements. Our results show an overlap with the distribution of outbreaks of porcine reproductive and respiratory syndrome, which is believed to be transmitted, at least in part, though animal movements. While the correspondence of movements and disease is not a causal test, it suggests that the predicted network may approximate actual movements. Accordingly, the predictions provided here might help to design and implement control strategies in the region. Additionally, the methodology here may be used to estimate contact networks for other livestock systems when only incomplete information regarding animal movements is available

    Desplazamiento cotidiano de estudiantes entre comunas de Chile: evidencia y recomendaciones de política para la nueva institucionalidad de la Educación Pública

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    Donoso-Diaz, S (Donoso-Diaz, Sebastian) ; Arias-Rojas, O (Arias-Rojas, Oscar). Univ Talca, Talca, Chile.A key feature of the Chilean school system is the discrimination in educational provision, showing a strong association between learning outcomes, on the one hand, and cultural capital and income of households, on the other. This discrimination forces families to seek educational institutions according to their expectations, generating mobility of students from their communities of origin to other communities. The analysis of the Chilean survey of households in 2006 allowed to quantify this phenomenon (student commuting), and demonstrated the existence of patterns associated with the dynamics of settlement of the population along the country: low mobility in the end regions, intermediate in the central regions of the country, and high in the Metropolitan Region of Santiago. According to these results, we discuss policy recommendations essential to incorporate the territorial dimension in the design of the new institutions of public education in Chile

    Accounting and international relations:Britain, Spain and the Asiento treaty

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    The boundaries between accounting and law are contingent on time–space intersections. Here, these margins are explored in the realm of international relations by focusing on the Asiento, an 18th century treaty granting Britain the monopoly to trade slaves with the Spanish American colonies. Although a relatively minor concern of treaty-makers, noncompliance with provisions of the Asiento by the South Sea Company placed accounting centre stage in conflicts between Britain and Spain. In combination with geo-strategic and domestic political circumstances, reporting failures exacerbated the commercial dispute between the two nations which culminated in war in 1739. The accounting provisions of the Asiento are examined by drawing on managerialist and realist theories of treaty compliance. It is shown that British noncompliance with accounting obligations under the treaty was driven by realist self-interest and the maximisation of material gain. Given that such motivations dominated behaviour attempts to manage noncompliance through the routine processes and structures of international politics proved unsuccessful. Managerial devices such as diplomatic exchanges over treaty ambiguity and securing greater informational transparency merely provided further opportunities for the pursuit of self-interest. It is suggested that divergent perceptions of the role of accounting in international relations stem from the unique political, legal, social and cultural configurations of nation states. The study highlights the limitations of accounting as an instrument of treaty verification. Its effectiveness in that capacity is diminished where there is no shared understanding of the significance, purpose, content and interpretation of accounting information

    Elaboracion y normalizacion de una prueba de habla comprimida en oraciones a un 40% de comprension

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    51 p.El procesamiento auditivo central (PAC) se entiende como los procesos del sistema nervioso central, para entender el mensaje. Actualmente no existen estudios hispanos y algunos pertenecientes a otros idiomas, que se encuentren validados, en la medición de la(s) habilidad(es) del procesamiento auditivo central; la misma realidad se repite en Chile. Por ello se presenta a continuación el proceso de elaboración y normalización de una prueba de habla comprimida en oraciones a un 40% de compresión, mediante el diseño y aplicación de una prueba que se adapta a la realidad lingüística chilena con el fin de obtener una prueba válida para medir el Procesamiento Auditivo Central en una población de personas jóvenes entre los 18 y 24 años de la Universidad de Talca en la carrera de Fonoaudiología. Además se explica detalladamente la metodología y los estímulos utilizados en la aplicación de la prueba; cómo fueron obtenidos y analizados los datos para su uso y mediante las conclusiones se detallarán los posteriores hallazgos con la finalidad de aportar información necesaria para futuros fines audiológicos en personas con Trastornos en el Procesamiento Auditivo Central (TPAC)

    Determinants of Teacher Quality: Pedagogical Excellence Accreditation Program

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    Garcia, LY (Garcia, Leidy Y.); Cerda, AA (Cerda, Arcadio A.); Donoso-Diaz, S (Donoso-Diaz, Sebastian)Teachers at primary and secondary schools constitute a hey factor in the educative process and learning results of their students. Given the constitutional mandate that defines the slate's responsibility to provide high-quality public education, it must attract. retain and motivate "good" teachers through diverse mechanisms and incentives, and in the Chilean case it must generate efficient mechanisms to evaluate their teaching performance. The Program to Reward Pedagogical Excellence (AEP from its Spanish acronym) conic about in this framework as a mechanism lot evaluation and incentives, because it aims to evaluate significant aspects of the quality of teachers, awarding bonuses to the roost outstanding. Given the importance of educational quality in establishments subsidized by the state (both municipal and private) for the development of the country and society, this work aims to determine the characteristics of teachers who have obtained ALP quality accreditation, through a conditional probit model using data from a longitudinal Teaching Survey (ELD from its Spanish acronym), while also calculating the probability of participating in this program. We conclude that the factors that explain the probability of being accredited are: experience, the family's socioeconomic condition. the mother's educational level, the teacher's educational level training and internships, quality of health conditions, vocation and quality of the AEP program, which have significant hut reduced effect

    Defences against brood parasites from a social immunity perspective

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    Parasitic interactions are so ubiquitous that all multicellular organisms have evolved a system of defences to reduce their costs, whether the parasites they encounter are the “classic parasites” that feed on the individual, or “brood parasites” that usurp parental care. Many parallels have been drawn between defences deployed against both types of parasite, but typically, whilst defences against classic parasites have been selected to protect survival, those against brood parasites have been selected to protect the parent’s inclusive fitness, suggesting that the selection pressures they impose are fundamentally different. However, there is another class of defences against classic parasites that have specifically been selected to protect an individual’s inclusive fitness, known as “social immunity”. Social immune responses include the anti-parasite defences typically provided for others in kin-structured groups, such as the antifungal secretions produced by termite workers to protect the brood. Defences against brood parasites, therefore, are more closely aligned with social immune responses. Much like social immunity, host defences against brood parasitism are employed by a donor (a parent) for the benefit of one or more recipients (typically kin), and as with social defences against classic parasites, defences have therefore evolved to protect the donor’s inclusive fitness, not the survival or ultimately the fitness of individual recipients This can lead to severe conflicts between the different parties, whose interests are not always aligned. Here we consider defences against brood parasitism in the light of social immunity, at different stages of parasite encounter, addressing where conflicts occur and how they might be resolved. We finish with considering how this approach could help us to address longstanding questions in our understanding of brood parasitism.Peer reviewe

    Tick-Borne Encephalitis Virus: A General Overview

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    Tick-borne encephalitis (TBE) virus is classified as one species with three subtypes, namely the European subtype, the Siberian subtype and the Far Eastern subtype. TBE is distributed in an endemic pattern of so-called natural foci over a wide geographical area from Western Europe to the northern part of Japan. It is the most important flavivirus infection of the central nervous system in Europe and Russia, with about 13,000 estimated human cases per year. The epidemiology of TBE is closely related to the ecology and biology of ixodid ticks. In nature, TBE virus is propagated in a cycle involving permanently infected ticks and wild vertebrate hosts. Currently, the diagnosis of TBE is mainly based on the detection of specific antibodies in serum and cerebrospinal fluid. No specific treatment for the disease is available to date, but it can be prevented by active immunization
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