1,768 research outputs found
Effect of hypoxia on lung gene expression and proteomic profile: insights into the pulmonary surfactant response
Exposure of lung to hypoxia has been previously reported to be associated with significant alterations in the protein content of bronchoalveolar lavage (BAL) and lung tissue. In the present work we have used a proteomic approach to describe the changes in protein complement induced by moderate long-term hypoxia (rats exposed to 10% O2 for 72h) in BAL and lung tissue, with a special focus on the proteins associated with pulmonary surfactant, which could indicate adaptation of this system to limited oxygen availability. The analysis of the general proteomic profile indicates a hypoxia-induced increase in proteins associated with inflammation both in lavage and lung tissue. Analysis at mRNA and protein levels revealed no significant changes induced by hypoxia on the content in surfactant proteins or their apparent oligomeric state. In contrast, we detected a hypoxia-induced significant increase in the expression and accumulation of hemoglobin in lung tissue, at both mRNA and protein levels, as well as an accumulation of hemoglobin both in BAL and associated with surface-active membranes of the pulmonary surfactant complex. Evaluation of pulmonary surfactant surface activity from hypoxic rats showed no alterations in its spreading ability, ruling out inhibition by increased levels of serum or inflammatory proteins.Ministerio de Ciencia BIO2012-30733Ministerio de Ciencia CSD2007-00010Gobierno de la Comunidad de Madrid S2009MAT-1507National Institutes of Health NIH HL3478
Waste clay materials as pozzolanic additions
En: 1st Spanish National Conference on Advances in Materials Recycling and Eco – Energy Madrid, 12-13 November 2009.-- Editors: F. A. López, F. Puertas, F. J. Alguacil and A. Guerrero.-- 4 pages, 3 figures.The building materials industries have made
improvements in manufacturing processes. However,
with the implementation of quality systems, more
compliance, with new standard more restrictive, and
especially by the competition between products, it is
inevitable that industries deemed a rejection of
material unsuitable for marketing or materials waste.
The wastes from the ceramic industry (ceramic
waste) may have characteristics suitable for use as
pozzolanic materials, as it is known that the first
materials used as pozzolans were heat-treated clays,
material like clay products.This research was funded by a Science and
Technology Commission (CICYT) (Research Project
AMB96-1095).Peer reviewe
Infección por Theileria annae en un perro esplenectomizado
La babesiosis canina es una enfermedad infecciosa de distribución mundial debida a la proliferación en los hematíes del perro de unas babesias específicas transmitidas por garrapatas. Si bien ha sido tradicionalmente asumido que las únicas especies que causan enfermedad en la especie canina son Babesia canis y Babesia gibsoni, publicaciones recientes demuestran que una tercera especie (Theileria annae) también puede causar una enfermedad muy severa. Este trabajo presenta el segundo caso publicado de esta forma de Theileria annae en un perro de 14 años, de raza Basset Hound, esplenectomizado cinco meses antes, que se presentó en la clínica veterinaria con signos de hipertermia, hemoglobinuria, temblores y apatía. El estudio de laboratorio constató una acusada anemia hemolítica regenerativa y una intensa trombocitopenia como datos más característicos. En la extensión de sangre periférica se visualizaron múltiples merozoítos intra (22%) y extraeritrocitarios de pequeño tamaño (1-2 micras), forma anular y presentación única en la mayoría de hematíes. La prontitud del diagnóstico y del tratamiento específico con dipropionato de imidocarb hizo que el cuadro clínico evolucionase con rapidez hacia la curación, en contra de lo que es habitual en los animales esplenectomizados.
Long photoperiod impairs learning in male but not female medaka
Day length in conjunction with seasonal cycles affects many aspects of animal biology. We have studied photoperiod-dependent alterations of complex behavior in the teleost, medaka (Oryzias latipes), a photoperiodic breeder, in a learning paradigm whereby fish have to activate a sensor to obtain a food reward.Medaka were tested under a long (14:10 LD) and short (10:14 LD) photoperiod in three different groups:mixed-sex, all-males, and all-females. Under long photoperiod, medaka mixed-sex groups learned rapidly with a stable response. Unexpectedly, males-only groups showed a strong learning deficit, whereas females- only groups performed efficiently. In mixed-sex groups, female individuals drove group learning, whereas males apparently prioritized mating over feeding behavior resulting in strongly reduced learning performance. Under short photoperiod, wheremedaka do notmate,male performance improved to a level similar to that of females. Thus, photoperiod has sex-specific effects on the learning performance of a seasonal vertebrate
Influence of freezing temperatures prior to freeze‐drying on viability of yeasts and lactic acid bacteria isolated from wine
Aims: To determine the effect of three different freezing temperatures on
post-freeze-drying survival rates of wine yeasts and lactic acid bacteria (LAB).
To know if a similar freeze-drying protocol can be used for both micro-
organisms.
Methods and Results: Cells from liquid culture media were recovered and
concentrated in appropriate lyoprotectants. Aliquots of each strain were frozen
at 20, 80 and 196°C before vacuum drying. Viable cell counts were done
before freezing and after freeze-drying. Survival rates were calculated. Freezing
temperatures differently affected yeast and bacteria survival. The highest
survival rates were obtained at 20 and 80°C for yeasts, but at 196° C for
LAB. Major differences in survival rates were recorded among freeze-dried
yeasts, but were less drastic for LAB. Yeasts Pichia membranifaciens, Starmerella
bacillaris and Metschnikowia pulcherrima, and LAB Lactobacillus paracasei,
Pediococcus parvulus and Lactobacillus mali, were the most tolerant species to
freeze-drying, regardless of freezing temperature.
Conclusions: Yeast and LAB survival rates differed for each tested freezing
temperature. For yeasts, 20°C ensured the highest post-freeze-drying viability
and 196°C for LAB.
Significance and Impact of the Study: Freezing temperature to freeze-dry cells
is a crucial factor for ensuring good wine yeast and LAB survival. These results
are important for appropriately preserving micro-organisms and for improving
starter production processes
The diurnal cycle of shallow cumulus clouds over land: A single-column model intercomparison study
An intercomparison study for single-column models (SCMs) of the diurnal cycle of shallow cumulus convection is reported. The case, based on measurements at the Atmospheric Radiation Measurement program Southern Great Plains site on 21 June 1997, has been used in a large-eddy simulation intercomparison study before. Results of the SCMs reveal the following general deficiencies: too large values of cloud cover and Cloud liquid water, unrealistic thermodynamic profiles, and high amounts of numerical noise. Results are also strongly dependent on vertical resolution.These results are analysed in terms of the behaviour of the different parametrization schemes involved: the convection scheme, the turbulence scheme, and the cloud scheme. In general the behaviour of the SCMs can be grouped in two different classes: one class with too strong mixing by the turbulence scheme, the other class with too strong activity by the convection scheme. The coupling between (subcloud) turbulence and the convection scheme plays a crucial role. Finally, (in part) motivated by these results several models have been successfully updated with new parametrization schemes and/or their present schemes have been successfully modifie
Babesia microti-like en un perro inmunocompetente
La babesiosis canina es una enfermedad infecciosa de distribución mundial causada por parásitos intraeritrocitarios transmitidos por garrapatas. Si bien ha sido tradicionalmente asumido que sólo dos de las 73 especies de babesias identificadas causan enfermedad en la especie canina, Babesia canis y Babesia gibsoni, recientes publicaciones demuestran que una tercera especie (Babesia microti-like) también puede parasitar a perros. Este último parásito, genéticamente relacionado con Babesia microti, es el origen de una enfermedad endémica entre la población canina del noroeste de España. Este trabajo presenta un caso no experimental de esta forma de Babesia microti-like en un perro cocker spaniel de 9 años, sin antecedentes de inmunodeficiencia ni de esplenectomía, que se presenta en la clínica veterinaria con signos de hipertermia, hemoglobinuria, escalofríos y apatía. Una muy intensa parasitemia (24%), junto con trombopenia y una acusada anemia hemolítica regenerativa fueron los hallazgos más caractéristicos. En la extensión de sangre periférica se visualizaron múltiples merozoitos intraeritrocitarios (parasitemia de un 24%) de pequeño tamaño (1-2 um) y presentación única en cada hematíe. Cuarenta y ocho horas después del comienzo de los síntomas, y tras tratamiento específico con dipropionato de imidocarb el perro evolucionó hacia la curación
Theoretical and experimental study of mechanical losses in automotive turbochargers
The aim of the present work is to show an approximation, through an experimental an theoretical study, to quantify
the mechanical losses in a turbocharging system. These are linked to the dynamics in the turbo shaft bearings, both
axial and radial. Theoretical and experimental methodologies are presented in order to develop a mechanical losses
model. The experimental work consists on a measurement campaign in quasi-adiabatic operating conditions, while in
the theoretical part, a mathematical model is developed taking into account the radial and axial bearings. The model
uses some assumptions in order to solve the Navier-Stokes equations, leading to a simplified model which includes
viscosity and the Reynolds number of the oil film formed on the bearings. The proposed model has shown a good
agreement with the experimental dataThe authors of this paper wish to thank M.A. Ortiz and V. Ucedo for their invaluable work during the experimental setup and campaign, F.J. Arnau, Ph.D, for its excellent job maintaining and expanding Open WAMs code base and M.A. Reyes-Belmonte for all his hard and rigorous work extrapolating turbine maps and preparing and launching the simulations. This work has been partially supported by the Spanish Ministerio de Ciencia e Innovacion through grant number DPI2010-20891-C02-02.Serrano Cruz, JR.; Olmeda González, PC.; Tiseira Izaguirre, AO.; García-Cuevas González, LM.; Lefebvre, A. (2013). Theoretical and experimental study of mechanical losses in automotive turbochargers. Energy. 55:888-898. https://doi.org/10.1016/j.energy.2013.04.042S8888985
Cognitive appraisal of environmental stimuli induces emotion-like states in fish
The occurrence of emotions in non-human animals has been the focus of debate over the years. Recently, an interest in expanding this debate to non-tetrapod vertebrates and to invertebrates has emerged. Within vertebrates, the study of emotion in teleosts is particularly interesting since they represent a divergent evolutionary radiation from that of tetrapods, and thus they provide an insight into the evolution of the biological mechanisms of emotion. We report that Sea Bream exposed to stimuli that vary according to valence (positive, negative) and salience (predictable, unpredictable) exhibit different behavioural, physiological and neuromolecular states. Since according to the dimensional theory of emotion valence and salience define a two-dimensional affective space, our data can be interpreted as evidence for the occurrence of distinctive affective states in fish corresponding to each the four quadrants of the core affective space. Moreover, the fact that the same stimuli presented in a predictable vs. unpredictable way elicited different behavioural, physiological and neuromolecular states, suggests that stimulus appraisal by the individual, rather than an intrinsic characteristic of the stimulus, has triggered the observed responses. Therefore, our data supports the occurrence of emotion-like states in fish that are regulated by the individual's perception of environmental stimuli.European Commission [265957 Copewell]; Fundacao para a Ciencia e Tecnologia [SFRH/BD/80029/2011, SFRH/BPD/72952/2010]info:eu-repo/semantics/publishedVersio
Sarcoptes scabiei infestation does not alter the stability of ectoparasite communities
BACKGROUND: The host represents a heterogeneous ecosystem where multiple parasite species co-occur and interact with each other for space and resources. Although these interactions may rule the features of an infracommunity and may shape the infracommunity response to external perturbations, the resilience of ectoparasite communities to new infestations remains poorly explored. METHODS: We analysed the composition of the ectoparasite communities found on 214 individual Iberian ibexes (Capra pyrenaica) inhabiting the Sierra Nevada Natural Space, southern Spain. Using classification and regression trees, we explored how the presence of Sarcoptes scabiei (a highly contagious mite), the off-host environment and the host sex govern the prevalence and abundance of lice and ticks. Null model analysis was applied to assess the impact of S. scabiei on the structure of the ectoparasite communities. RESULTS: Our results suggest that S. scabiei infestation acts in tandem with off-host environment and host sex to define the prevalence and abundance of lice and ticks. We also provided evidence for differences in species co-occurrence only at the early stages of S. scabiei infestation. Regarding species diversity, we recorded that ectoparasite communities in scabietic ibexes reached a high richness faster than those in healthy individuals. CONCLUSIONS: Even though we show that ectoparasite burden is correlated with S. scabiei infestation, off-host environment and host sex, the species response to S. scabiei infestation and climate seem to be highly variable and influenced by ectoparasite life-history traits. Ectoparasite communities also appear resilient to perturbations which is in agreement with what was previously reported for endoparasites. Future refinement of sample collection and the incorporation of ecological and epidemiological-related variables may allow us to establish causal effects and deepen the knowledge about the mechanisms and consequences of ectoparasite interactions
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