187 research outputs found

    Effet de l’huile d’olive, de tournesol ou de graines de lin sur le patron de fermentation et la production de méthane dans le système de simulation ruminale RUSITEC

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    6 páginas, 2 tablas.-- Contributed to: 13th Seminar of the FAO-CIHEAM Sub-Network on Sheep and Goat Nutrition: Challenging strategies to promote sheep and goat sector in the current global (León, Spain, oct 14-16, 2009).The objective of this study was to investigate the effects of the addition of different vegetable oils to the diet on the fermentation pattern and methane production in Rusitec fermenters. For this purpose four treatments were randomly allocated to sixteen fermenters in a completely random design. Inoculum was obtained from four ruminally fistulated Merino sheep fed lucerne hay and concentrate. Treatments were defined by the diet supplied to the fermenters, so that the control treatment (C) diet was a total mixed ration for ewes on lactation. In the other experimental treatments the control diet was supplemented with olive oil (OO), sunflower oil (SO) or linseed oil (LO) to reach a final concentration of 50 g oil/kg diet. After 7 days of adaptation, samples of effluent, fermenters’ fluid content and digesta of each fermenter were collected during 10 days. There were no significant differences (P>0.05) between treatments in pH values in the fermenters’ fluid content. The LO diet showed (P0.05). All three oils reduced methane production compared with control cultures (P0.05) of oil supplementation on Llactate concentration. Ammonia N concentration was higher (P<0.05) in the control treatment, but there were no significant differences between treatments in microbial protein output. In conclusion, these results indicate that fermentation pattern is affected by oil supplementation mainly by decreasing the acetate to propionate ratio, as well as methane production.Funding received from Spanish MICINN (Projects AGL2008-04805 and AGL2005-04760) and from Junta de Castilla y León (Project GR158) is gratefully acknowledged.Peer Reviewe

    SHAPE Project Vortex Bladeless: Parallel multi-code coupling for Fluid-Structure Interaction in Wind Energy Generation

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    Vortex-Bladeless is a Spanish SME whose objective is to develop a new concept of wind turbine without blades called Vortex or vorticity wind turbine. This design represents a new paradigm in wind energy and aims to eliminate or reduce many of the existing problems in conventional generators. Due to the significant difference in the project concept, its scope is different from conventional wind turbines. It is particularly suitable for offshore configuration and it could be exploited in wind farms and in environments usually closed to existing ones due to the presence of high intensity winds. The device is composed of a single structural component, and given its morphological simplicity, its manufacturing, transport, storage and installation has clear advantages. The new wind turbine design has no bearings, gears, etcetera, so the maintenance requirements could be drastically reduced and their lifespan is expected to be higher than traditional wind turbines. It is clear that the proposed device is of prime interest, and that scientific investigation of the response of this wind energy generator under different operation scenarios is highly desirable. Thus, the objective of this SHAPE project is to develop the needed tools to simulate Fluid-Structure Interaction (FSI) problems and to reproduce the experimental results for scaled models of the Vortex-Bladeless device. In order to do so the Alya code, developed at the Barcelona Supercomputing Center, is adapted to perform the Fluid-Structure Interaction (FSI) problem simulation. The obtained numerical results match satisfactorily with the experimental results reported.This work was financially supported by the PRACE project funded in part by the EU’s Horizon 2020 research and innovation programme (2014-2020) under grant agreement 653838.Postprint (published version

    Technical note:The persistence of microbial-specific DNA sequences through gastric digestion in lambs and its potential use as microbial markers

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    Two groups of 5 lambs were euthanized at the weaning (T45) and fattening stages (T90) to evaluate the use of microbial ribosomal DNA (rDNA) sequences as potential microbial markers in relation to purine bases (PB) as a conventional marker. Both microbial markers originated similar microbial N concentrations (mg/g of DM), although T45 showed decreased values compared with the T90 group when either PB or rDNA were considered (P = 0.02). The survival of microbial rDNA was determined in 3 digestive sites (omasum, abomasum, and duodenum), but no substantial differences were observed, indicating that rDNA maintains the molecular stability along the sampling sites analyzed. Contrarily PB concentration increased successively along the digestive tract (P < 0.05), likely as a consequence of the endogenous PB secretion. Undegraded milk PB may also explain the overestimation of the microbial N concentration (2.8 times greater) using PB than rDNA sequences. Abomasum was the sampling site where the best agreement between PB and rDNA estimations was observed. Protozoal N concentration was irrelevant in T45 animals, although substantial in T90 lambs (18% of microbial N). In conclusion, bacterial 16S and protozoal 18S rDNA sequences may persist through the gastric digestive tract and their utilization as a highly specific microbial marker should not be neglected.This study was supported by a FPU grant from the Education and Science Spanish Ministry (project: AGL 2004-02910/GAN) and by a University of Zaragoza project (UZ2008-BIO-04)

    Nuevas citas de Mauremys leprosa y Trachemys scripta en la provincia de Málaga

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    Este trabajo ha sido parcialmente financiado por el proyecto CGL2009-11316 y por una beca de Formación de Profesorado Universitario del Ministerio de educación AP2007-03633.Peer reviewe

    Characterization of a clinical olfactory test with an artificial nose

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    Clinical olfactory tests are used to address hyposmia/anosmia levels in patients with different types of olfactory impairments. Typically, a given test is employed clinically and then replaced by a new one after a certain period of use which can range from days to several months. There is a need to assess control quality of these tests and also for a procedure to quantify their degradation over time. In this paper we propose a protocol to employ low-cost artificial noses for the quantitative characterization of olfactory tests used in clinical studies. In particular, we discuss a preliminary study on the Connecticut Chemosensorial Clinical Research Center Test kit which shows that some odorants, as sensed by an artificial nose, seem to degrade while others are potentiated as the test ages. We also discuss the need to establish a map of correspondence between human and machine olfaction when artificial noses are used to characterize or compare human smell performance in research and clinical studies

    La Oscilación del Atlántico Norte y la temperatura superficial del mar afectan la abundancia de la tortuga boba alrededor del estrecho de Gibraltar

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    The aim of this study was to explore the possible link between variations in the North Atlantic Oscillation (NAO) and sea surface temperature (SST) and the abundance of loggerhead turtles around the Strait of Gibraltar, using stranding data for the Andalusian coastal area as a proxy for abundance. The annual average SST (from November to October) in the Gulf of Cadiz was negatively associated with the total number of loggerhead strandings each year from November 1997 to October 2006 in the Gulf of Cadiz and the Alboran Sea. The average NAO index was positively associated with the number of strandings in the Gulf of Cadiz in the following year. Prevailing westerly winds during positive NAO phases and the subsequent delayed decrease in SST may lead to turtles from the west Atlantic accumulating in the Gulf of Cadiz and unsuccessfully attempting to return. Secondary causes, such as buoyancy, cold stunning, longline fisheries, net fisheries, debilitated turtle syndrome, and trauma may also increase the number of turtle strandings.El objetivo de este estudio fue explorar la posible relación entre las variaciones de la Oscilación del Atlántico Norte (NAO) y la temperatura superficial del mar (SST), y la abundancia de tortugas bobas alrededor del Estrecho de Gibraltar, utilizando los datos de varamientos como sustituto de la abundancia. La SST promedio en el Golfo de Cádiz se relacionó negativamente con el número total de tortugas bobas varadas durante cada año (de noviembre a octubre) desde 1997 hasta 2006 en el Golfo de Cádiz y en el Mar de Alborán, mientras que el promedio del índice NAO se relacionó positivamente con el número de varamientos en el Golfo de Cádiz durante el año siguiente. Vientos predominantes del oeste durante las fases de la NAO positiva, y su posterior retraso en la reducción de la SST, pueden provocar la acumulación en el Golfo de Cádiz de las tortugas que entran desde el Atlántico occidental y, las que sin éxito, tratan de regresar a sus playas de origen. Debido a causas secundarias (como problemas de flotabilitdad, enfriamiento, la pesca con palangre, la pesca con redes, DTS, y traumatismos) aumenta el número de tortugas varadas

    Multi-omics in vitro study of the salivary modulation of the goat rumen microbiome

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    Ruminants are able to produce large quantities of saliva which enter into the rumen and salivary components exert different physiological functions. Although previous research has indicated that salivary immunoglobulins can partially modulate the rumen microbial activity, the role of the salivary components other than ions on the rumen microbial ecosystem has not been thoroughly investigated in ruminants. To investigate this modulatory activity, a total of 16 semi-continuous in vitro cultures with oats hay and concentrate were used to incubate rumen fluid from four donor goats with autoclaved saliva (AUT) as negative control, saliva from the same rumen fluid donor (OWN) as positive control, and either goat (GOAT) or sheep (SHEEP) saliva as experimental interventions. Fermentation was monitored throughout 7 days of incubation and the microbiome and metabolome were analysed at the end of this incubation by Next-Generation sequencing and liquid chromatography coupled with mass spectrometry, respectively. Characterisation of the proteome and metabolome of the different salivas used for the incubation showed a high inter-animal variability in terms of metabolites and proteins, including immunoglobulins. Incubation with AUT saliva promoted lower fermentative activity in terms of gas production (−9.4%) and highly divergent prokaryotic community in comparison with other treatments (OWN, GOAT and SHEEP) suggesting a modulatory effect derived from the presence of bioactive salivary components. Microbial alpha-diversity at amplicon sequence variant (ASV) level was unaffected by treatment. However, some differences were found in the microbial communities across treatments, which were mostly caused by a greater abundance of Proteobacteria and Rikenellacea in the AUT treatment and lower of Prevotellaceae. These bacteria, which are key in the rumen metabolism, had greater abundances in GOAT and SHEEP treatments. Incubation with GOAT saliva led to a lower protozoal concentration and propionate molar proportion indicating a capacity to modulate the rumen microbial ecosystem. The metabolomics analysis showed that the AUT samples were clustered apart from the rest indicating different metabolic pathways were promoted in this treatment. These results suggest that specific salivary components contribute to host-associated role in selecting the rumen commensal microbiota and its activity. These findings could open the possibility of developing new strategies to modulate the saliva composition as a way to manipulate the rumen function and activity

    El campo de las y los defensores de derechos humanos en México La estructura de posiciones en el campo

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    Segundo momento del análisis del campo de las y los defensores de derechos humanos en México en el que se hace una descripción muy general de las posiciones que ocupan los agentes más relevantes en materia de derechos humanos, o para violentarlos de manera estructural y sistemática o, por el contrario, para defenderlos y protegerlos.ITESO, A.C
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