23 research outputs found

    Crecimiento y eficiencia de uso del nitrógeno en maíz de regadío en una región semiárida según la fertilización nitrogenada utilizada

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    The main groundwater pollution factor in irrigated maize production areas is leaching of nitrogen below the root zone. During the years 1999-2001, experiments were carried out on irrigated maize in the semiarid region of Castilla- La Mancha to evaluate the effect of nitrogen in the growth and yield of maize. Three rates of nitrogen were tested: No (0 kg N ha-1), Nop (175, 150 and 130 kg N ha-1 in 1999, 2000 and 2001, respectively), and Nc (300 kg N ha-1). A high initial level of residual soil NO-3 was found in the spring of 1999 as a consequence of fertilization carryover from the previous years. Although there was no plant response to N fertilization in 1999, significant responses were obtained during the following two years. Moreover, in 2000, the grain production did not show significant differences between Nop and Nc. However, in 2001, maize yield was slightly decreased due to an attempt to decrease the Nop to 130 kg N ha-1, showing significant differences with regard to Nc. The differences in grain yield among nitrogen levels were mainly due to a significant variation in maximum leaf area index, leaf area duration and crop growth rate. There was a decreasing pattern in nitrogen use efficiency values with increasing fertilizer rates, indicating that crop production could be sustained with lower fertilizer applications. Fertilizer practices must be revised in order to control and prevent insofar as possible water pollution in "La-Mancha Oriental" aquifer.El principal contaminante del agua subterránea en las áreas de regadío cultivadas de maíz es la lixiviación del nitrógeno. Durante los años 1999 a 2001 se han realizado ensayos en maíz regado en la región semiárida de Castilla-La Mancha, con el objetivo de evaluar su producción y crecimiento ante tres dosis de nitrógeno: No (0 kg N ha-1), Nop (175, 150 y 130 kg N ha-1 en 1999, 2000 y 2001, respectivamente), y Nc (300 kg N ha-1). El alto nivel inicial de NO-3 residual en el suelo durante la primavera de 1999, consecuencia de la fertilización anterior, propició la falta de respuesta a la fertilización con N. Sin embargo, se obtuvieron respuestas significativas los dos años siguientes. Además, en el año 2000, la producción de grano no registró diferencias significativas entre Nop y Nc. Sin embargo, disminuyó ligeramente la producción en el año 2001 al tratar de reducir la dosis óptima a 130 kg N ha-1, presentando diferencias significativas respecto a Nc. Este hecho fue debido, principalmente, a una variación significativa en el índice de área foliar máximo, la duración del área foliar y la tasa de crecimiento del cultivo. Las dosis más elevadas de fertilizante originaron una disminución de la eficiencia de uso del nitrógeno, por lo que la producción podría obtenerse con unos aportes menores de nitrógeno. Se debe revisar la fertilización para contribuir a controlar y prevenir, en la medida de lo posible, la contaminación en el acuífero de La Mancha Oriental

    Trehalose-based siamese twin amphiphiles with tunable self-assembling, DNA nanocomplexing and gene delivery properties

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    An original family of multivalent vectors encompassing gemini and facial amphiphilicity, namely cationic Siamese twin surfactants, has been prepared fromthe disaccharide trehalose; molecular engineering lets us modulate the self-assembling properties and the topology of the nanocomplexes with plasmid DNA for efficient gene delivery in vitro and in vivo

    Spanish guidelines for the use of targeted deep sequencing in myelodysplastic syndromes and chronic myelomonocytic leukaemia

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    The landscape of medical sequencing has rapidly changed with the evolution of next generation sequencing (NGS). These technologies have contributed to the molecular characterization of the myelodysplastic syndromes (MDS) and chronic myelomonocytic leukaemia (CMML), through the identification of recurrent gene mutations, which are present in >80% of patients. These mutations contribute to a better classification and risk stratification of the patients. Currently, clinical laboratories include NGS genomic analyses in their routine clinical practice, in an effort to personalize the diagnosis, prognosis and treatment of MDS and CMML. NGS technologies have reduced the cost of large-scale sequencing, but there are additional challenges involving the clinical validation of these technologies, as continuous advances are constantly being made. In this context, it is of major importance to standardize the generation, analysis, clinical interpretation and reporting of NGS data. To that end, the Spanish MDS Group (GESMD) has expanded the present set of guidelines, aiming to establish common quality standards for the adequate implementation of NGS and clinical interpretation of the results, hoping that this effort will ultimately contribute to the benefit of patients with myeloid malignancies

    MCR-ALS on metabolic networks: Obtaining more meaningful pathways

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    [EN] With the aim of understanding the flux distributions across a metabolic network, i.e. within living cells, Principal Component Analysis (PCA) has been proposed to obtain a set of orthogonal components (pathways) capturing most of the variance in the flux data. The problems with this method are (i) that no additional information can be included in the model, and (ii) that orthogonality imposes a hard constraint, not always reasonably. To overcome these drawbacks, here we propose to use a more flexible approach such as Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS) to obtain this set of biological pathways through the network. By using this method, different constraints can be included in the model, and the same source of variability can be present in different pathways, which is reasonable from a biological standpoint. This work follows a methodology developed for Pichia pastoris cultures grown on different carbon sources, lately presented in González-Martínez et al. (2014). In this paper a different grey modelling approach, which aims to incorporate a priori knowledge through constraints on the modelling algorithms, is applied to the same case of study. The results of both models are compared to show their strengths and weaknesses.Research in this study was partially supported by the Spanish Ministry of Science and Innovation and FEDER funds from the European Union through grants DPI2011-28112-C04-01 and DPI2011-28112-C04-02. The authors are also grateful to Biopolis SL for supporting this research.Folch-Fortuny, A.; Tortajada Serra, M.; Prats-Montalbán, JM.; Llaneras Estrada, F.; Picó Marco, JA.; Ferrer Riquelme, AJ. (2015). MCR-ALS on metabolic networks: Obtaining more meaningful pathways. Chemometrics and Intelligent Laboratory Systems. 142:293-303. https://doi.org/10.1016/j.chemolab.2014.10.004S29330314

    HTLV-1 infection in solid organ transplant donors and recipients in Spain

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    HTLV-1 infection is a neglected disease, despite infecting 10-15 million people worldwide and severe illnesses develop in 10% of carriers lifelong. Acknowledging a greater risk for developing HTLV-1 associated illnesses due to immunosuppression, screening is being widely considered in the transplantation setting. Herein, we report the experience with universal HTLV testing of donors and recipients of solid organ transplants in a survey conducted in Spain. All hospitals belonging to the Spanish HTLV network were invited to participate in the study. Briefly, HTLV antibody screening was performed retrospectively in all specimens collected from solid organ donors and recipients attended since the year 2008. A total of 5751 individuals were tested for HTLV antibodies at 8 sites. Donors represented 2312 (42.2%), of whom 17 (0.3%) were living kidney donors. The remaining 3439 (59.8%) were recipients. Spaniards represented nearly 80%. Overall, 9 individuals (0.16%) were initially reactive for HTLV antibodies. Six were donors and 3 were recipients. Using confirmatory tests, HTLV-1 could be confirmed in only two donors, one Spaniard and another from Colombia. Both kidneys of the Spaniard were inadvertently transplanted. Subacute myelopathy developed within 1 year in one recipient. The second recipient seroconverted for HTLV-1 but the kidney had to be removed soon due to rejection. Immunosuppression was stopped and 3 years later the patient remains in dialysis but otherwise asymptomatic. The rate of HTLV-1 is low but not negligible in donors/recipients of solid organ transplants in Spain. Universal HTLV screening should be recommended in all donor and recipients of solid organ transplantation in Spain. Evidence is overwhelming for very high virus transmission and increased risk along with the rapid development of subacute myelopathy

    Estudios de marcado y recaptura de especies marinas

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    Los resultados obtenidos del marcado y posterior recaptura de los ejemplares son una herramienta muy valiosa para contribuir a mejorar el conocimiento de la biología y ecología de una especie, examinando ciertos aspectos como son: el crecimiento, los movimientos o migraciones, la mortalidad o supervivencia, la abundancia y distribución de la especie, el hábitat y diferenciación de poblaciones o stocks. Actualmente la técnica de marcado se aplica a muchas especies, tanto terrestres como marinas, pertenecientes a diversos grupos zoológicos: peces, crustáceos, reptiles, moluscos y mamíferos. Este libro repasa algunos ejemplos de marcado de especies marinas de interés comercial. No todas las especies pueden ser marcadas, porque es necesario cumplir una serie de requisitos para poder llevar a cabo con éxito un experimento de marcado. En uno de los apartados de esta guía, se describen los distintos aspectos a tener en cuenta para obtener buenos resultados. Se describen los principales proyectos de marcado actualmente en ejecución o en marcha llevados a cabo por el Instituto Español de Oceanografía (IEO). En primer lugar, se describe brevemente la especie, su distribución, crecimiento, reproducción, alimentación, etc. A continuación, se presenta la información del marcado, es decir, campañas realizadas, número de ejemplares marcados y algunos de los resultados obtenidos hasta la fecha a partir de las recapturas disponibles. En algunas especies, los programas de marcado se llevan realizando desde hace más de 20 años, como es el caso del atún rojo, por lo que la información disponible es bastante amplia. En otros casos por el contrario como la merluza, los proyectos son relativamente recientes, no obstante los resultados son bastante interesantes y prometedores.Nowadays many different marine animals are being tagged. This book summarizes recent tagging programs carried out by the Spanish Institute of Oceanography (IEO). Although the objectives of these various studies mainly depend on the species and each project in particular, the general aim is to better understand the biology and ecology of these animals the structure and dynamics of their populations and their capacity to respond to human activities. This book provides an overview of different aspects of this technique such as a brief history of tagging, the types of tags currently used, including both conventional and electronic tags, where and how to put them on the marine animals, some recommendations regarding how to perform a tagging survey and where to go or what to do if anyone recovers a tagged fish or marine animal. The book then summarizes the main species tagged by the IEO, making a short description of their biology followed by some of the results obtained from tagging studies undertaken until now. Other applications are to know the spatial distribution (spawning or feeding areas), estimate growth parameters, mortality and survival rates, longevity, the size of the population or identifying stocks. Nowadays the advances in electronics have also open new fields such us the possibility of tracking an animal and knowing its habitat preferences and behaviour. Besides some of these tags have the capacity of recording this information during long periods and sending the data from long distances even without the need to recover the animal. Tagging activities constitute a very useful tool to improve the knowledge of many species and contribute to their management and conservation. For that reason this methodology is included in many IEO projects in which other activities like the monitoring of the fishery (landings, fishing effort, fleet characteristics, fishing areas, biological sampling, etc.) are carried out. Some projects are related with coastal pelagic fisheries including anchovy, sardine and mackerel or oceanic pelagic fisheries like tuna and billfish species and pelagic sharks. Others are focused on benthic and demersal species such as hake, black spot seabream, anglerfish, flatfish, etc. Nevertheless not all species can be tagged, as they have to survive being caught and handled before being release. For this reason, tagging techniques may not easily be applied to some species.Versión del edito

    CFD modeling of oxy-coal combustion: Prediction of burnout, volatile and NO precursors release

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    The devolatilisation step of coal is a vital stage in both air–coal and oxy-coal combustion and there is interest in whether methods of estimating the reaction parameters are similar for both cases. A network pyrolysis model, the FG-DVC (Functional Group-Depolymerisation Vaporisation Cross-linking) code was employed to evaluate the effect of temperature (1273–1773 K) and heating rate (104–106 K/s) on the devolatilisation parameters of two coals of different rank. The products distribution between char and volatiles, and volatiles and NH3/HCN release kinetics were also determined. In order to assess the accuracy of the FG-DVC predictions, the values for nitrogen distribution and devolatilisation kinetics obtained for a temperature of 1273 K and a heating rate of 105 K/s were included as inputs in a Computational Fluid Dynamics (CFD) model for oxy-coal combustion in an entrained flow reactor (EFR). CFD simulations with the programme default devolatilisation kinetics were performed. The oxygen content in oxy-firing conditions ranged between 21% and 35%, and air-firing conditions were also employed as a reference. The experimental coals burnouts and oxygen concentrations from the EFR experiments were employed to test the accuracy of the CFD model. The temperature profiles, burning rates, char burnout and NO emissions during coal combustion in both air and O2/CO2 atmospheres were predicted. The predictions obtained when using the CFD model with FG-DVC coal devolatilisation kinetics were much closer to the experimental values than the predictions obtained with the ANSYS Fluent (version 12) program default kinetics. The predicted NO emissions under oxy-firing conditions were in good agreement with the experimental values.The present study was carried out with financial support from the Spanish MICINN (Project PS-120000-2005-2) co-financed by the European Regional Development Fund. L.A. and J.R. acknowledge funding from the CSIC JAE program, which was cofinanced by the European Social Fund, and the Asturias Regional Government (PCTI program), respectively. MG acknowledges financial support from E.ON UK, and for an EPSRC Dorothy Hodgkin Postgraduate Award. We also thank Dr L Ma for helpful discussions.Peer reviewe

    HTLV-1 infection in solid organ transplant donors and recipients in Spain

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    Background: HTLV-1 infection is a neglected disease, despite infecting 10–15 million people worldwide and severe illnesses develop in 10% of carriers lifelong. Acknowledging a greater risk for developing HTLV-1 associated illnesses due to immunosuppression, screening is being widely considered in the transplantation setting. Herein, we report the experience with universal HTLV testing of donors and recipients of solid organ transplants in a survey conducted in Spain. Methods: All hospitals belonging to the Spanish HTLV network were invited to participate in the study. Briefly, HTLV antibody screening was performed retrospectively in all specimens collected from solid organ donors and recipients attended since the year 2008. Results: A total of 5751 individuals were tested for HTLV antibodies at 8 sites. Donors represented 2312 (42.2%), of whom 17 (0.3%) were living kidney donors. The remaining 3439 (59.8%) were recipients. Spaniards represented nearly 80%. Overall, 9 individuals (0.16%) were initially reactive for HTLV antibodies. Six were donors and 3 were recipients. Using confirmatory tests, HTLV-1 could be confirmed in only two donors, one Spaniard and another from Colombia. Both kidneys of the Spaniard were inadvertently transplanted. Subacute myelopathy developed within 1 year in one recipient. The second recipient seroconverted for HTLV-1 but the kidney had to be removed soon due to rejection. Immunosuppression was stopped and 3 years later the patient remains in dialysis but otherwise asymptomatic. Conclusion: The rate of HTLV-1 is low but not negligible in donors/recipients of solid organ transplants in Spain. Universal HTLV screening should be recommended in all donor and recipients of solid organ transplantation in Spain. Evidence is overwhelming for very high virus transmission and increased risk along with the rapid development of subacute myelopathy

    Spanish guidelines for the use of targeted deep sequencing in myelodysplastic syndromes and chronic myelomonocytic leukaemia

    No full text
    The landscape of medical sequencing has rapidly changed with the evolution of next generation sequencing (NGS). These technologies have contributed to the molecular characterization of the myelodysplastic syndromes (MDS) and chronic myelomonocytic leukaemia (CMML), through the identification of recurrent gene mutations, which are present in >80% of patients. These mutations contribute to a better classification and risk stratification of the patients. Currently, clinical laboratories include NGS genomic analyses in their routine clinical practice, in an effort to personalize the diagnosis, prognosis and treatment of MDS and CMML. NGS technologies have reduced the cost of large-scale sequencing, but there are additional challenges involving the clinical validation of these technologies, as continuous advances are constantly being made. In this context, it is of major importance to standardize the generation, analysis, clinical interpretation and reporting of NGS data. To that end, the Spanish MDS Group (GESMD) has expanded the present set of guidelines, aiming to establish common quality standards for the adequate implementation of NGS and clinical interpretation of the results, hoping that this effort will ultimately contribute to the benefit of patients with myeloid malignancies

    The stratigraphical record and activity of evaporite dissolution subsidence in Spain

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