481 research outputs found

    Acoustic methods for Gelidium seaweed detection

    Get PDF
    Se han realizado mediciones del coeficiente de reflexión y absorción de una capa espesa de algas de Gelidium sesquipedale (Clem. Born. et Thur.), sobre un fondo de arena, dispuesto en un tanque de experiencias hidroacústicas. Como resultado de la reducida sección transversal acústica de cada brote del alga, y de su alto contenido de agua, su impedancia acústica tiene un valor muy próximo a la impedancia acústica del agua marina y, en consecuencia, el nivel de blanco de cada brote es muy débil. El rango de frecuencias utilizado parte de 100 kHz, alcanzando 500 kHz. El valor promedio del nivel de difusión de fondo de la capa de alga de Gelidium encontrado varía entre -26 dB y -34 dB en el rango de frecuencias utilizado.The reflection and absorption coefficients of a thick layer of Gelidium sesquipedale (Clem. Born. et Thur.) seaweed covering a sandy bottom were determined in a laboratory tank. As a result of the reduced vertical cross-section and the high water content of this seaweed, its acoustical impedance is very similar to water impedance, and the target strength of each individual seaweed frond is very weak. The usual frequency range for detection of marine life, 100-500 kHz, has been used. The average value of the bottom scattering strength was found to be between -26 dB and -34 dB in the frequency band used.Instituto Español de Oceanografí

    Un model de formació continuada, reflexiu i participatiu

    Get PDF
    Els reptes que planteja avui la comprensió del món, posen en evidència que cal una alfabetització científica i didàctica dels i de les mestres d’educació infantil i primària. La nostra experiència en formació ens porta a afirmar que aquests grans reptes cal abordar-los des d’una perspectiva socioconstructivista de la formació. El model de formació que presentem pretén donar resposta a les necessitats del professorat, en relació als coneixements i a la didàctica de les ciències. Proposa aprofundir en la reflexió sobre la pròpia pràctica i sobre noves propostes metodològiques, a fi d’actualitzar i millorar les competències tecnocientífiques

    Allosteric Conversation in the Androgen Receptor Ligand-Binding Domain Surfaces

    Get PDF
    Androgen receptor (AR) is a major therapeutic target that plays pivotal roles in prostate cancer (PCa) and androgen insensitivity syndromes. Wepreviously proposed that compounds recruited to ligand-binding domain (LBD) surfaces could regulate AR activity in hormone-refractory PCa and discovered several surface modulators of AR function. Surprisingly, the most effective compounds bound preferentially to a surface of unknown function [binding function 3 (BF-3)] instead of the coactivator-binding site [activation function 2 (AF-2)]. Different BF-3 mutations have been identified in PCa or androgen insensitivity syndrome patients, and they can strongly affect AR activity. Further, comparison of AR x-ray structures with and without bound ligands at BF-3 and AF-2 showed structural coupling between both pockets. Here, we combine experimental evidence and molecular dynamic simulations to investigate whether BF-3 mutations affect AR LBD function and dynamics possibly via allosteric conversation between surface sites. Our data indicate that AF-2 conformation is indeed closely coupled to BF-3 and provide mechanistic proof of their structural interconnection. BF-3 mutations may function as allosteric elicitors, probably shifting the AR LBD conformational ensemble toward conformations that alter AF-2 propensity to reorganize into subpockets that accommodate N-terminal domain and coactivator peptides. The induced conformation may result in either increased or decreased AR activity. Activating BF-3 mutations also favor the formation of another pocket (BF-4) in the vicinity of AF-2 and BF-3, which we also previously identified as a hot spot for a small compound. We discuss the possibility that BF-3 may be a protein-docking site that binds to the N-terminal domain and corepressors. AR surface sites are attractive pharmacological targets to develop allosteric modulators that might be alternative lead compounds for drug design. © 2012 by The Endocrie Society

    Presentación. Antiguas y nuevas perspectivas sobre el final de los tiempos

    Get PDF
    -

    Macromicetes de la comarca del Berguedá (Barcelona)

    Get PDF
    Se da cuenta de ciento cuarenta y ocho especies de macromicetes recolectadas en el transcurso de una serie de excursiones de estudio, realizadas por los autores entre los años 1974 al 1977, por diversas localidades de la comarca del Berguedá (Barcelona).Numerosas especies entre las indicadas fueron recolectadas en varias ocasiones, lo que permitió apreciar detalles de su comportamiento autoecológico.En todos los casos hemos pretendido confirmar las determinaciones taxonómicas utilizando los medios reseñados en la Bibliografia. De cada especie se dispone de su ficha de estudio, con los detalles apreciados al realizar la determinanción, pese a ello no hemos considerado adecuado dar descripciones por no hacer más extenso el presente trabajo.We remark the determinations of a hundred and forty eight species of Macromycets collected the year 1974 to the 1977, mainly in Berguedá district (Barcelona).Most of them could be studied more than once. We tried to confirm the determinations using the last specialized works

    Aportaciones al catálogo florístico de la provincia de León II

    Get PDF
    Se enumeran 512 especies vegetales de la provincia de León (España) recogidas en 693 localidades, se hacen breves asociaciones ecológicas de las mismas, así como de su distribución y comportamiento fitosociológico. Se realiza, al mismo tiempo, la revisión bibliográfica a nivel provincial

    Impact of climate change environmental conditions on the resilience of different formulations of the biocontrol agent Candida sake CPA‐1 on grapes

    Get PDF
    Biocontrol agents have become componentsof integrated crop protection systemsfor controlling economically important fungal pathogens.Candida sakeCPA-1 is abiocontrol agent of fungal pathogens of fruits, both pre- and post-harvest. Whilethe efficacy of different formulations have been examined previously, few studieshave considered the resilience of different formulations under changing climaticconditions of elevated temperature, drought stress and increased atmospheric CO2.This study examined the effect of (a) temperature9RH9elevated CO2(400vs1000 ppm) on the temporal establishment and viability of two dry and one liquidC. sakeCPA-1 formulations on grape berry surfaces; (b) temperature stress (25vs35°C); and (c) elevated CO2levels. Results indicated that temperature, RH and CO2concentration influenced the establishment and viability of the formulations butthere was no significant difference between formulations. For the combined three-component factors, increased temperature (35°C) and lower RH (40%) reduced theviable populations on grapes. The interaction with elevated CO2improved theestablishment of viable populations of the formulations tested. Viable populationsgreater than Log 4 CFUs per g were recovered from the grape surfaces suggestingthat these had conserved resilience for control ofBotrytisrot in grapes.info:eu-repo/semantics/acceptedVersio

    Ellagic acid: Biological properties and biotechnological development for production processes

    Get PDF
    Ellagic acid, 2,3,7,8-tetrahydroxy-chromeno[5,4,3-cde]chromene-5,10-dione, is a powerful bioactive compound with many potential pharmacological and industrial applications. In this review, the chemical aspects, biological properties and diverse potential applications of ellagic acid for different industries were described. This review also discussed the advance in ellagitannin biodegradation, focusing on the process of isolation of microorganisms and strain selection, medium and culture optimization, as well as fermentation systems for commercially viable industrial scale production. The performances of various fermentation techniques that have been applied for the production of ellagic acid from residual by-products were compared, while the advantages and disadvantages of each plant source were also discussed.Key words: Ellagic acid, ellagitannin, biodegradation, fungal physiology, solid-state fermentation, submerged fermentation

    Predicted ecological niches and environmental resilience of different formulations of the biocontrol yeast Candida sake CPA-1 using the Bioscreen C

    Get PDF
    Environmental resilience of biocontrol microorganisms has been a major bottleneck in the development of effective formulations. Candida sake is an effective biocontrol agent (BCA) against Penicillium expansum, Botrytis cinerea or Rhizopus stolonifer, and different formulations of the BCA have been optimised recently. The objective of this study was to compare the relative tolerance of different dry and liquid formulations of the biocontrol yeast C. sake CPA-1 to interacting environmental conditions using the Bioscreen C. Initially, the use of this automated turbidimetric method was optimised for use with different formulations of the biocontrol yeast. The best growth curves were obtained for the C. sake CPA-1 strain when grown in a synthetic grape juice medium under continuous shaking and with an initial concentration of 105 CFUs ml−1. All the formulations showed a direct relationship between optical density values and yeast concentrations. Temperature (15–30 °C) and water activity (aw; 0.94–0.99) influenced the yeast resilience most profoundly, whereas the effect of pH (3–7) was minimal. In general, the liquid formulation grew faster in more interacting environmental conditions but only the yeast cells in the dry potato starch formulation could grow in some stress conditions. This rapid screening method can be used for effective identification of the resilience of different biocontrol formulations under interacting ecological abiotic conditions.info:eu-repo/semantics/acceptedVersio

    Precise OBS location at the sea bottom in active seismic profiles using the air gun shot records

    Get PDF
    The Norcaribe campaign, in November – December 2013, funded by Spanish Ministry of Innovation and Science (Norcaribe Project CGL2010-17715), was performed on board of the Spanish research vessel “Sarmiento de Gamboa” around the Hispaniola island, also with the participation of the Dominic Republic Navy patrol vessels and several Haiti and Dominic Republic institutions. During the campaign, a 200 km long, wide-amgle refraction seismic profile was carried out crossing the Beata ridge. The air gun signal (5100 ci) was recorded by 15 OBSs deployed along the seismic line in water depths between 2.300 meters and 4.320 meters. To obtain the section records, the OBS position is needed, usually the deployment location is used, but the OBS can drift while is sinking due to the deep oceanic currents. The recovery locations at surface could provide information about the drift, assuming a constant sea current since the deployment to the recovery, but it is imprecise. In this work we show a method to obtain a precise location of the OBS at the sea bottom using a high-resolution bathymetry and the OBS record of the closest air gun shots of the profile. Also, the preliminary results for the Norcaribe campaign (Beata ridge profile) are shown.Peer Reviewe
    corecore