Mechanisms Contributing to the Emergence of Ranavirus in Ectothermic Vertebrate Communities

Ranaviruses have been linked to amphibian die-off events in ectothermic vertebrates worldwide. Differences in susceptibility and capacity of transmission among and within classes are poorly understood. My goal was to determine possible mechanisms influencing susceptibility to ranavirus infection in amphibian species and other aquatic vertebrate taxa, as well as the capacity of transmission between classes and the effects of amphibian community composition on ranavirus transmission. I tested 16 amphibian species from USA, Europe, and the pet trade, expanding an existing database developed by the Center for Wildlife Health to 35 amphibian species from 9 families. I also tested the susceptibility of 5 fish and 3 turtle species by exposure to a panel of ranaviruses from amphibian, fish and reptilian hosts under laboratory conditions. I used outdoor aquatic mesocosms to explore if certain species functioned as amplification hosts in a semi-natural environment. All vertebrate classes tested (amphibian, reptile, and fish) presented variability in susceptibility. Amphibians were most susceptible to ranavirus, but no phylogenetic relationship with susceptibility was detected. Susceptibility was related to life history characteristics of amphibian hosts. Fast-developing species that bred in temporary wetlands during spring showed higher susceptibility to ranavirus. Further, for one of the isolates, pathogenicity increased as distance between host population and isolate location increased. Fish and turtle species showed low susceptibility to ranavirus, but could function as reservoirs for ranavirus due to documentation of subclinical infections. Transmission experiments demonstrated that ranavirus could be transmitted between classes, with greatest mortality when infected turtles or fish transmitted the virus to amphibians. Finally, I showed that community composition affects ranavirus transmission and mortality in larval amphibians. Wood frog larvae functioned as amplification hosts to spotted salamander (Ambystoma maculatum) and caused an outbreak in chorus frog (Pseudacris feriarum). My results demonstrate that ranaviruses can infect multiple hosts from different classes with different susceptibilities, contributing to its persistence in the environment and recurrent outbreaks. My results can be used to identify potential species of high risk to ranaviral disease and highlight the need to understand host community to predict ranavirus outbreaks and develop conservation strategies to mitigate emergence of ranaviral disease

EFFECTIVENESS OF ALTERNATIVE EXPORT PROMOTION STRATEGIES FOR BRANDED FOOD PRODUCTS

This study examines the impact on export sales of various promotional strategies for branded food products in foreign markets. It is an empirical analysis using data obtained from organizations that administer the High Value Export Incentive Program (HVEIP) for branded food products, part of USDA's Targeted Export Assistance (TEA) program and its successor, the Marketing Assistance Program (MAP). To respect the proprietary nature of the data, the identity of individual firms and brand names has been deleted and products have been combined into two groups: (1) consumer ready and (2) intermediate. Economic analysis reveals positive and statistically significant impacts of expenditures on television advertising and advertising in consumer-orientated print media on export sales of consumer ready products, the effect of the latter being somewhat larger. No other promotional strategy reveals a consistent and statistically significant relationship to exports. Channel-orientated strategies seldom showed positive results on export levels for consumer ready products, and consumer-orientated strategies bear no detectable relationship to export levels of intermediate products.International Relations/Trade,

Copula selection models for non-Gaussian responses that are missing not at random

Missing not at random (MNAR) data poses key challenges for statistical inference because the model of interest is typically not identifiable without imposing further (e.g., distributional) assumptions. Sample selection models have been routinely used for handling MNAR by jointly modelling the outcome and selection variables assuming that these follow a bivariate normal distribution. Recent studies have advocated parametric selection model approaches, for example estimated by multiple imputation and maximum likelihood, that are more robust to departures from the normality assumption. However, the proposed methods have been mostly restricted to a specific joint distribution (e.g., bivariate t-distribution). This paper discusses a flexible copula-based selection approach (which accommodates a wide range of non-Gaussian outcome distributions and offers great flexibility in the choice of functional form specifications for both the outcome and selection equations) and proposes a flexible imputation procedure that generates plausible imputed values from the copula selection model. A simulation study characterises the relative performance of the copula model compared with the most commonly used selection models for estimating average treatment effects with MNAR data. We illustrate the methods in the REFLUX study, which evaluates the causal effect of laparoscopic surgery compared to usual medical management on long-term quality of life in patients with reflux disease. We provide software code for implementing the proposed copula framework using the R package GJRM

The incorporation and use of ICT in early childhood education. A study on infrastructure, teachihng methods and teacher training in Andalusia

El objetivo de este artículo es presentar los resultados de un estudio realizado durante el curso 2015-16 sobre la dotación tecnológica con que cuentan las aulas de Educación Infantil en Andalucía, el uso didáctico de los recursos TIC que realizan los docentes, y su formación y actitudes hacia las tecnologías en los procesos de enseñanza y aprendizaje. Aunque existe abundante investigación sobre la etapa de Educación Primaria, Secundaria y en la enseñanza universitaria, resulta palpable la ausencia de estudios en la primera etapa de escolarización en la vida de los niños y niñas. Los datos se recabaron mediante una encuesta en línea respondida por una muestra de 163 maestros/as. Las conclusiones apuntan que la dotación tecnológica de los centros es insuficiente, que tan solo una tercera parte de la muestra de docentes utiliza las TIC de manera cotidiana en el aula, y que el 70% demanda mayor cualificación, y considera que este tipo de recursos son potenciadores de mayor aprendizaje.The aim of this article is to present the results of a recent study on the technological equipment of preschool classrooms in Andalusia, the educational use of ICT resources by teachers and their training and attitudes towards technologies in the process of teaching and learning. Although there is an abundant research on the stage of primary, secondary and university education, it is clear the lack of studies in the first stage of schooling in the lives of children. Data are collected through an online survey answered by a sample of 163 teachers. The conclusions indicate that the provision is insufficient, ICT are used on a daily basis in the classroom only a third of the simple and that 70% of teachers demand higher qualifications and consider that these resources are enhancers higher learning

Efecto de la impregnación al vacío sobre los cambios físicos durante la elaboración de aceitunas de mesa

Among the benefits which vacuum impregnation (VI) may provide to fruits and vegetables, this study focused on weight and texture changes during the processing of table olives. VI applied to Manzanilla olives led to around 10% weight gain, which was maintained after their packing as black olives. However, this weight gain was only around 4 % for Hojiblanca olives. Likewise, the use of calcium chloride was recommended to maintain the firmness of the olives, in particular those of the softer Manzanilla cultivar. With regard to the Spanish-style, the Hojiblanca cultivar achieved around 4% weight gain during processing but the use of VI for Manzanilla olives was ruled out due to softening of the fruit. In addition. the black and green color of olives and their flavor were not modified by the application of VI. This technology could be very useful to reduce weight loss during table olive processing.Entre los beneficios que la aplicación de la impregnación al vacío puede originar en frutas y verduras, este estudio se ha centrado sobre los cambios en la textura y el peso de las aceitunas de mesa durante su procesamiento. La impregnación al vacío de aceitunas Manzanilla dio lugar a un aumento cercano al 10 % de peso y ello se mantuvo después de su envasado como aceitunas negras, mientras que esta ganancia fue de sólo el 4& para aceitunas Hojiblanca. Asimismo, se vio necesario el empleo de cloruro cálcico para el mantenimiento de la textura de los frutos, en particular para aquellos de la variedad Manzanilla. Con respecto al procesamiento como verdes estilo español, la variedad Hojiblanca consiguió un aumento del 4% en peso debido al empleo de impregnación al vacío y este tratamiento se descartó para la Manzanilla debido al ablandamiento de la aceituna. Además, se debe indicar que el color verde y negro de las aceitunas no se vio afectado por el hecho de emplear impregnación al vacío. Esta tecnología podría ser muy útil para reducir las pérdidas de peso que se producen durante la elaboración de aceitunas de mesa

Un análisis de las industrias de refinación del aceite de oliva en Andalucía

This work studies the economic relationships between the industries of refining and other links of the foodprocessing chain of the olive oil. In addition, the principal components of the cost structure of the refining and packaging processes are analyzed. Also, an analysis of the evolution followed by the participation of the foreign investment in the share capital of the refining industries is included. Finally, the strategies that the industries of refining are developing on the market in origin are commented.Este trabajo estudia las relaciones económicas que se establecen entre las industrias de refinación y los demás eslabones de la cadena agroalimentaria del aceite de oliva. Además, se analizan los principales componentes de la estructura de costes del proceso de refinación y envasado. Asimismo, comprende un análisis de la evolución que ha seguido la participación de la inversión extranjera en el capital social de las industrias de refinación. Por último, incluye las estrategias que en la actualidad las industrias de refinación están desarrollando en el mercado en origen

Agroforestería

Documento PDF, 45 páginasGuía de estudio para el curso Agroforestería, código 0878, que se imparte en el programa Manejo de Recursos Naturales de la UNED.Universidad Estatal a Distancia de Costa Ric

INDIGO : better geomagnetic observatories where we need them

The INDIGO project aims to improve the global coverage of digital observatories by deploying digital magnetometer systems in: i) Observatories where existing analog recording equipment is in need of upgrading. ii) Newly established digital observatories. iii) Existing digital observatories for the purpose of quality control and redundancy. In implementing the project and selecting suitable sites, special attention is paid to parts of the Earth devoid of magnetic observatories, increasing the reliability and long-term operation of existing observatories and cost-effective use of local resources. The Poster reviews the current status of the project. We examine the different steps and initiatives taken since the initiation of INDIGO in 2004 and assess their effectiveness in achieving progress towards our aims of improving global coverage and enhanced data quality

High-Throughput System for the Early Quantification of Major Architectural Traits in Olive Breeding Trials Using UAV Images and OBIA Techniques

The need for the olive farm modernization have encouraged the research of more efficient crop management strategies through cross-breeding programs to release new olive cultivars more suitable for mechanization and use in intensive orchards, with high quality production and resistance to biotic and abiotic stresses. The advancement of breeding programs are hampered by the lack of efficient phenotyping methods to quickly and accurately acquire crop traits such as morphological attributes (tree vigor and vegetative growth habits), which are key to identify desirable genotypes as early as possible. In this context, an UAV-based high-throughput system for olive breeding program applications was developed to extract tree traits in large-scale phenotyping studies under field conditions. The system consisted of UAV-flight configurations, in terms of flight altitude and image overlaps, and a novel, automatic, and accurate object-based image analysis (OBIA) algorithm based on point clouds, which was evaluated in two experimental trials in the framework of a table olive breeding program, with the aim to determine the earliest date for suitable quantifying of tree architectural traits. Two training systems (intensive and hedgerow) were evaluated at two very early stages of tree growth: 15 and 27 months after planting. Digital Terrain Models (DTMs) were automatically and accurately generated by the algorithm as well as every olive tree identified, independently of the training system and tree age. The architectural traits, specially tree height and crown area, were estimated with high accuracy in the second flight campaign, i.e. 27 months after planting. Differences in the quality of 3D crown reconstruction were found for the growth patterns derived from each training system. These key phenotyping traits could be used in several olive breeding programs, as well as to address some agronomical goals. In addition, this system is cost and time optimized, so that requested architectural traits could be provided in the same day as UAV flights. This high-throughput system may solve the actual bottleneck of plant phenotyping of "linking genotype and phenotype," considered a major challenge for crop research in the 21st century, and bring forward the crucial time of decision making for breeders