Surveillance studies of Lymphocystis disease virus in farmed gilthead seabream (Sparus aurata) by real-time PCR

Lymphocystis disease (LCD) is the main viral infection reported to affect cultured gilthead seabream (Sparus aurata) in Southern Atlantic and Mediterranean aquaculture. Its etiological agent is the Lymphocystis disease virus (LCDV), a member of the family Iridoviridae (genus Lymphocystivirus). The only adequate measures for LCD prevention in the aquaculture systems are general prophylactic practices, such as the control of fish to be introduced in the farm facilities in order to detect carrier fish. These animals may pose a risk for the introduction of LCDV in fish farms, as direct contact between fish specimens is considered the main route of LCDV spreading. More recently, asymptomatic carrier breeders, as well as virus contaminated-live food, have been involved in LCDV transmission to fish larvae. The detection of subclinical viral infections in carrier fish requires the use of sensitive diagnostic methods. In this context, the objective of this study was to establish the applicability of a real-time PCR assay for LCDV diagnosis in surveillance studies. In addition, the assay has been evaluated with samples from a gilthead seabream hatchery, in order to prove its utility to trace the origin of LCDV in fish farms. Juvenile fish were collected at four farms with different background regarding to LCD. LCDV was detected in all farms, and 30 to 100% of fish were identified as LCDV-infected. Estimated viral load in caudal fin of asymptomatic fish was two to five orders of magnitude lower than in diseased fish. Carrier fish were also identified in the broodstock from a farm with LCD records by analysing caudal fin samples by qPCR. In this farm, the q-PCR assay developed in this study allowed the quantitative detection of LCDV in all samples collected in the hatchery, including fertilized eggs, larvae and fingerlings, and also rotifer cultures and artemia metanauplii and cysts used for larval rearing.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Enhancing declarative process models with DMN decision logic

Modeling dynamic, human-centric, non-standardized and knowledge-intensive business processes with imperative process modeling approaches is very challenging. Declarative process modeling approaches are more appropriate for these processes, as they offer the run-time flexibility typically required in these cases. However, by means of a realistic healthcare process that falls in the aforementioned category, we demonstrate in this paper that current declarative approaches do not incorporate all the details needed. More specifically, they lack a way to model decision logic, which is important when attempting to fully capture these processes. We propose a new declarative language, Declare-R-DMN, which combines the declarative process modeling language Declare-R with the newly adopted OMG standard Decision Model and Notation. Aside from supporting the functionality of both languages, Declare-R-DMN also creates bridges between them. We will show that using this language results in process models that encapsulate much more knowledge, while still offering the same flexibility

Course of infection with Lymphocystis disease virus in gilthead seabream (Sparus aurata)

Lymphocystis disease virus (LCDV) is the etiological agent of lymphocystis disease (LCD), a pathology that affects a wide variety of fish species. Data about LCDV pathogenesis are very short, and mainly limited to histopathological studies of skin lesions. Recent studies on viral genome detection (both by PCR or DNA-DNA in situ hybridization) suggest that LCDV establish a systemic and persistent infection in gilthead seabream (Sparus aurata), but further studies are necessary to prove if this infection is productive or not. In the present study viral quantification and viral mRNA detection (by qPCR and RT-qPCR) have been used to investigate LCDV multiplication in different organs of juvenile gilthead seabream. In addition, a histopathological study was carried out. Animals were collected from two commercial farms in Southwestern Spain. In one farm, where no LCD outbreaks have been recorded, apparently healthy fish were collected, whereas in the other farm, diseased and recovered (two months after LCD symptoms disappearance) fish were sampled. All the animals were LCDV-infected, and viral gene expression was detected in every organ analysed (caudal fin, intestine, liver, spleen, kidney and brain). In asymptomatic animals, both apparently healthy and recovered, a low-titre infection was observed, with the highest viral copy numbers detected in brain and kidney. In diseased fish, viral loads were significantly higher than in subclinical infected animals, being maximal in caudal fin, where lymphocysts were present in the dermis. Different histological alterations were observed in the internal organs from diseased fish analysed, although no hypertrophied cells were detected in any of them. In recovered fish, most of the organs examined presented similar histological features to those in healthy animals. Thus, pathological changes were only detected in the intestine and liver, although they were less severe than those observed in diseased fish. The results presented showed that LCDV establishes a systemic infection in juvenile gilthead seabream, which can be subclinical. In addition, although the disease is self-limiting, the virus is not removed after disease recovery, but produces a persistent infection.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Extending Qualitative Spatial Theories with Emergent Spatial Concepts: An Automated Reasoning Approach

Qualitative Spatial Reasoning is an exciting research field of the Knowledge Representation and Reasoning paradigm whose application often requires the extension, refinement or combination of existent theories (as well as the associated calculus). This paper addresses the issue of the sound spatial interpretation of formal extensions of such theories; particularly the interpretation of the extension and the desired representational features. The paper shows how to interpret certain kinds of extensions of Region Connection Calculus (RCC) theory. We also show how to rebuild the qualitative calculus of these extensions.Junta de Andalucía TIC-606

An investigation of silicon carbide-water nanofluid for heat transfer applications

Thermal conductivity and mechanical effects of silicon carbide nanoparticles uniformly dispersed in water were investigated. Mean size of SiC particles was 170 nm with a polydispersity of 30% as determined from small-angle x-ray scattering and dynamic light scattering techniques. Room temperature viscosity of the nanofluids ranged from 2 to 3 cP for nominal nanoparticle loadings 4 – 7 vol %. On a normalized basis with water, viscosity of the nanofluids did not significantly change with the test temperature up to 85 °C. Optical microscopy of diluted nanofluid showed no agglomeration of the nanoparticles. Thermal conductivity of the fluid was measured as a function of the nominal nanoparticle loading ranging from 1 to 7 vol %. Enhancement in thermal conductivity was approximately 28% over that of water at 7 vol % particle loadings under ambient conditions. Enhancements in thermal conductivities for the nanofluids with varying nanoparticle loadings were maintained at test temperatures up to 70 °C. Results of thermal conductivity have been rationalized based on the existing theories of heat transfer in fluids. Implications of using this nanofluid for engineering cooling applications are discussed.Universidad de Chicago Argonne LLC (EE. UU.)-DE-AC02-06CH1135

Determinación de órganos diana para la multiplicación y persistencia del virus de la enfermedad de linfocistis (LCDV) en dorada (Sparus aurata, L.)

La enfermedad de linfocistis es la única patología de etiología viral descrita en dorada cultivada En la cuenca mediterr nea, la prevalencia es cercana al 100 , ocasionando graves p rdidas económicas debido a la imposibilidad de comercializar los peces afectados En el presente trabajo se ha abordado el estudio de la patog nesis del virus de la enfermedad de linfocistis (LCDV) en dorada, además se han establecido los órganos implicados en la multiplicación vírica Para ello, se ha diseñado un protocolo de hibridación in situ empleando sondas RNA marcadas con digoxigenina dirigidas contra el gen que codifica la proteína principal de la cápside (MCP) viral, y se ha evaluado en poblaciones de dorada. En paralelo, se ha procedido a la cuantificación del número de copias de genoma viral por PCR a tiempo real y cuantificación relativa de la transcripción del gen que codifica la MCP viral mediante qRT-PCR. Los resultados obtenidos indican que el LCDV establece una infección sistémica en alevines de dorada, pudiendo detectarse señal de hibridación tanto en órganos internos (hígado, bazo, riñón) como en músculo y aleta. También se han observado diversos daños histopatológicos en animales enfermos, mientras que en animales recuperados de la enfermedad estos daños parecen revertir, aunque en estos animales la infección persiste, si bien sólo a niveles detectables mediante PCR a tiempo real.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Desarrollo de un chip de DNA para la detección de dianas génicas bacterianas de interés en el campo de la acuicultura

La adquisición bacteriana de multiresistencias frente a antimicrobianos es un fenómeno cada vez más preocupante, con gran repercusión para la salud pública, pero también con impacto en sectores de la producción animal, como es el caso particular de la acuicultura. Entre los años 2010-2012, como objetivo de un Proyecto de Investigación Italiano (Progetti d’interesse Nazionale, PRIN), se realizaron diferentes campañas de muestreo a lo largo de la costa del mar Adriático, en centros dedicados a la acuicultura y áreas costeras, estudiando la incidencia de bacterias multiresistentes, así como de los elementos genéticos móviles responsables de su adquisición, desarrollando además una herramienta biotecnológica que agiliza este tipo de estudios permitiendo detectar 164 dianas génicas en un único soporte. Se obtuvo una colección de 1274 aislados bacterianos, a partir de muestras de agua, sedimento y biofilm, resistentes a las distintas combinaciones de antibióticos utilizados según la legislación italiana. Del total, 105 (8,25%) aislados resultaron ser multiresistentes, detectándose en el 13,59% el integrón de clase I, en el 14,56% el plásmido pAb5s9, en el 5,82% el elemento SXT/R391, y en el 15,52% diferentes combinaciones de estos elementos genéticos. Basándonos en estos resultados, se ha desarrollado y validado un chip de DNA que permite detectar en un mismo soporte, genes que codifican para determinantes de resistencia a antimicrobianos, elementos genéticos móviles (MGE), genes para la detección de especies bacterianas patógenas con repercusión en acuicultura y para la salud del hombre, e indicadores de contaminación fecal.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Fatigue behaviour of nanoclay reinforced epoxy resin composites

Nanoparticle filling is a feasible way to increase the mechanical properties of polymer matrices. Abundant research work has been published in the last number of years concerning the enhancement of the mechanical properties of nanoparticle filled polymers, but only a reduced number of studies have been done focusing on the fatigue behaviour. This work analyses the influence of nanoclay reinforcement and water presence on the fatigue behaviour of epoxy matrices. The nanoparticles were dispersed into the epoxy resin using a direct mixing method. The dispersion and exfoliation of nanoparticles was characterised by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Fatigue strength decreased with the nanoclay incorporation into the matrix. Fatigue life of nanoclay filled composites was significantly reduced by the notch effect and by the immersion in water

Development Process and Cognitive Testing of CARATkids - Control of Allergic Rhinitis and Asthma Test for Children

Background: Allergic rhinitis and asthma (ARA) are chronic inflammatory diseases of the airways that often coexist in children. The only tool to assess the ARA control, the Control of Allergic Rhinitis and Asthma Test (CARAT) is to be used by adults. We aimed to develop the Pediatric version of Control of Allergic Rhinitis and Asthma Test (CARATkids) and to test its comprehensibility in children with 4 to 12 years of age. Methods: The questionnaire development included a literature review of pediatric questionnaires on asthma and/or rhinitis control and two consensus meetings of a multidisciplinary group. Cognitive testing was carried out in a cross-sectional qualitative study using cognitive interviews. Results: Four questionnaires to assess asthma and none to assess rhinitis control in children were identified. The multidisciplinary group produced a questionnaire version for children with 17 questions with illustrations and dichotomous (yes/no) response format. The version for caregivers had 4-points and dichotomous scales. Twenty-nine children, 4 to 12 years old, and their caregivers were interviewed. Only children over 6 years old could adequately answer the questionnaire. A few words/expressions were not fully understood by children of 6 to 8 years old. The drawings illustrating the questions were considered helpful by children and caregivers. Caregivers considered the questionnaire complete and clear and preferred dichotomous over the 4-points scales. The proportion of agreement between children and their caregivers was 61%. The words/expressions that were difficult to understand were amended. Conclusion: CARATkids, the first questionnaire to assess a child’s asthma and rhinitis control was developed and its content validity was assured. Cognitive testing showed that CARATKids is well-understood by children 6 to 12 years old. The questionnaire’s measurement properties can now be assessed in a validation study