81 research outputs found

    Identification and localization of calcium-dependent protease II in Neurospora crassa and Uromyces appendiculatus

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    Summary: The existence of Ca2+-dependent protease II in crude extracts ofNeurospora crassa andUromyces appendiculatus was demonstrated by immunoblotting using specific antibodies. In both extracts two immunoreacting bands were observed. The molecular mass of the major band inN. crassa corresponded to 37 kDa, while that inU. appendiculatus was 43 kDa, similar to that previously reported forAllomyces arbuscula. Immunofluorescence of the enzyme was predominantly localized in the apical regions of germlings and growing hyphae, suggesting a functional role for the enzyme in hyphal growt

    Purification of a 47-kDa calmodulin-binding polypeptide as an actin-binding protein from Neurospora crassa

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    We have enriched a 47-kDa polypeptide (p47) from Neurospora crassa on the basis of its affinity to calmodulin. The p47 was purified to homogeneity by chromatography on a Mono S cation exchange column and evidence is presented that the polypeptide co-sediments specifically with F-actin. The intracellular distribution of p47 and actin was also examined using indirect double immunofluorescence staining of cells at different stages of development. Our results suggest that by altering the conformation binding site of actin to p47, calmodulin could play a regulatory role in the polarized hyphal growth of N. crass

    Effects of lindane on the photosynthetic apparatus of the cyanobacterium anabaena

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    Intention, Goal, Scope, Background: Cyanobacteria have the natural ability to degrade moderate amounts of organic pollutants. However, when pollutant concentration exceeds the level of tolerance, bleaching of the cells and death occur within 24 hours. Under stress conditions, cyanobacterial response includes the short-term adaptation of the photosynthetic apparatus to light quality, named state transitions. Moreover, prolonged stresses produce changes in the functional organization of phycobilisomes and in the core-complexes of both photosystems, which can result in large changes in the PS II fluorescence yield. The localization of ferredoxin-NADP+ reductase (FNR) at the ends of some peripheral rods of the cyanobacterial phycobilisomes, makes this protein a useful marker to check phycobilisome integrity. Objective: The goal of this work is to improve the knowledge of the mechanism of action of a very potent pesticide, lindane (γ-hexaclorociclohexane), in the cyanobacteriumAnabaena sp., which can be considered a potential candidate for bioremediation of pesticides. We have studied the effect of lindane on the photosynthetic apparatus ofAnabaena using fluorescence induction studies. As ferredoxin-NADP+ reductase plays a key role in the response to oxidative stress in several systems, changes in synthesis, degradation and activity of FNR were analyzed. Immunolocalization of this enzyme was used as a marker of phycobilisome integrity. The knowledge of the changes caused by lindane in the photosynthetic apparatus is essential for rational further design of genetically-modified cyanobacteria with improved biorremediation abilities. Methods: Polyphasic chlorophylla fluorescence rise measurements (OJIP) have been used to evaluate the vitality and stress adaptation of the nitrogen-fixing cyanobacteriumAnabaena PCC 7119 in the presence of increasing concentrations of lindane. Effects of the pesticide on the ultrastructure have been investigated by electron microscopy, and FNR has been used as a marker of phycobilisome integrity. Results and Discussion: Cultures ofAnabaena sp. treated with moderate amounts of lindane showed a decrease in growth rate followed by a recovery after 72 hours of pesticide treatment. Concentrations of lindane below 5 ppm increased the photosynthetic performance and activity of the cells. Higher amounts of pesticide caused a decrease in these activities which seems to be due to a non-competitive inhibition of PS II. Active PS II units are converted into non-QA reducing, so called heat sink centers. Specific activity and amount of FNR in lindane-treated cells were similar to the values measured in control cultures. Release of FNR from the thylakoid after 48 hours of exposure to 5 ppm of lindane towards the cytoplasm was detected by immunogold labeling and electron microscopy. Conclusions: From these results, we conclude that the photosynthetic performance and activity of the cells are slightly increased in the presence of lindane up to 5 ppm. Moreover, in those conditions, iindane did not produce significant changes in the synthesis, degradation or activity of FNR. The high capability ofAnabaena to tolerate lindane makes this cyanobacterium a good candidate for phytoremediation of polluted areas. Recommendation and Outlook: The results of this study show that cultures ofAnabaena PCC 7119 tolerate lindane up to 5 ppm, without significant changes in the photosynthetic vitality index of the cells. However, a slight increase in phycobiliprotein synthesis is observed, which is related to total protein content. This change might be due to degradation of proteins less stable than phycobiliproteins. An identification of the proteins with altered expression pattern in the presence of the pesticide remains the subject of further work and will provide valuable information for the preparation of strains which are highly tolerant to lindan

    Accurate Landing of Unmanned Aerial Vehicles Using Ground Pattern Recognition

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    [EN] Over the last few years, several researchers have been developing protocols and applications in order to autonomously land unmanned aerial vehicles (UAVs). However, most of the proposed protocols rely on expensive equipment or do not satisfy the high precision needs of some UAV applications such as package retrieval and delivery or the compact landing of UAV swarms. Therefore, in this work, a solution for high precision landing based on the use of ArUco markers is presented. In the proposed solution, a UAV equipped with a low-cost camera is able to detect ArUco markers sized 56×56 cm from an altitude of up to 30 m. Once the marker is detected, the UAV changes its flight behavior in order to land on the exact position where the marker is located. The proposal was evaluated and validated using both the ArduSim simulation platform and real UAV flights. The results show an average offset of only 11 cm from the target position, which vastly improves the landing accuracy compared to the traditional GPS-based landing, which typically deviates from the intended target by 1 to 3 m.This work was funded by the Ministerio de Ciencia, Innovación y Universidades, Programa Estatal de Investigación, Desarrollo e Innovación Orientada a los Retos de la Sociedad, Proyectos I+D+I 2018 , Spain, under Grant RTI2018-096384-B-I00.Wubben, J.; Fabra Collado, FJ.; Tavares De Araujo Cesariny Calafate, CM.; Krzeszowski, T.; Márquez Barja, JM.; Cano, J.; Manzoni, P. (2019). Accurate Landing of Unmanned Aerial Vehicles Using Ground Pattern Recognition. Electronics. 8(12):1-16. https://doi.org/10.3390/electronics8121532S116812Pan, X., Ma, D., Jin, L., & Jiang, Z. (2008). Vision-Based Approach Angle and Height Estimation for UAV Landing. 2008 Congress on Image and Signal Processing. doi:10.1109/cisp.2008.78Tang, D., Li, F., Shen, N., & Guo, S. (2011). UAV attitude and position estimation for vision-based landing. Proceedings of 2011 International Conference on Electronic & Mechanical Engineering and Information Technology. doi:10.1109/emeit.2011.6023131Gautam, A., Sujit, P. B., & Saripalli, S. (2014). A survey of autonomous landing techniques for UAVs. 2014 International Conference on Unmanned Aircraft Systems (ICUAS). doi:10.1109/icuas.2014.6842377Holybro Pixhawk 4 · PX4 v1.9.0 User Guidehttps://docs.px4.io/v1.9.0/en/flight_controller/pixhawk4.htmlGarrido-Jurado, S., Muñoz-Salinas, R., Madrid-Cuevas, F. J., & Medina-Carnicer, R. (2016). Generation of fiducial marker dictionaries using Mixed Integer Linear Programming. Pattern Recognition, 51, 481-491. doi:10.1016/j.patcog.2015.09.023Romero-Ramirez, F. J., Muñoz-Salinas, R., & Medina-Carnicer, R. (2018). Speeded up detection of squared fiducial markers. Image and Vision Computing, 76, 38-47. doi:10.1016/j.imavis.2018.05.004ArUco: Augmented reality library based on OpenCVhttps://sourceforge.net/projects/aruco/Jin, S., Zhang, J., Shen, L., & Li, T. (2016). On-board vision autonomous landing techniques for quadrotor: A survey. 2016 35th Chinese Control Conference (CCC). doi:10.1109/chicc.2016.7554984Chen, X., Phang, S. K., Shan, M., & Chen, B. M. (2016). System integration of a vision-guided UAV for autonomous landing on moving platform. 2016 12th IEEE International Conference on Control and Automation (ICCA). doi:10.1109/icca.2016.7505370Nowak, E., Gupta, K., & Najjaran, H. (2017). Development of a Plug-and-Play Infrared Landing System for Multirotor Unmanned Aerial Vehicles. 2017 14th Conference on Computer and Robot Vision (CRV). doi:10.1109/crv.2017.23Shaker, M., Smith, M. N. R., Yue, S., & Duckett, T. (2010). Vision-Based Landing of a Simulated Unmanned Aerial Vehicle with Fast Reinforcement Learning. 2010 International Conference on Emerging Security Technologies. doi:10.1109/est.2010.14Araar, O., Aouf, N., & Vitanov, I. (2016). Vision Based Autonomous Landing of Multirotor UAV on Moving Platform. Journal of Intelligent & Robotic Systems, 85(2), 369-384. doi:10.1007/s10846-016-0399-zPatruno, C., Nitti, M., Petitti, A., Stella, E., & D’Orazio, T. (2018). A Vision-Based Approach for Unmanned Aerial Vehicle Landing. Journal of Intelligent & Robotic Systems, 95(2), 645-664. doi:10.1007/s10846-018-0933-2Baca, T., Stepan, P., Spurny, V., Hert, D., Penicka, R., Saska, M., … Kumar, V. (2019). Autonomous landing on a moving vehicle with an unmanned aerial vehicle. Journal of Field Robotics, 36(5), 874-891. doi:10.1002/rob.21858De Souza, J. P. C., Marcato, A. L. M., de Aguiar, E. P., Jucá, M. A., & Teixeira, A. M. (2019). Autonomous Landing of UAV Based on Artificial Neural Network Supervised by Fuzzy Logic. Journal of Control, Automation and Electrical Systems, 30(4), 522-531. doi:10.1007/s40313-019-00465-ySITL Simulator (Software in the Loop)http://ardupilot.org/dev/docs/sitl-simulator-software-in-the-loop.htmlFabra, F., Calafate, C. T., Cano, J.-C., & Manzoni, P. (2017). On the impact of inter-UAV communications interference in the 2.4 GHz band. 2017 13th International Wireless Communications and Mobile Computing Conference (IWCMC). doi:10.1109/iwcmc.2017.7986413MAVLink Micro Air Vehicle Communication Protocolhttp://qgroundcontrol.org/mavlink/startFabra, F., Calafate, C. T., Cano, J. C., & Manzoni, P. (2018). ArduSim: Accurate and real-time multicopter simulation. Simulation Modelling Practice and Theory, 87, 170-190. doi:10.1016/j.simpat.2018.06.009Careem, M. A. A., Gomez, J., Saha, D., & Dutta, A. (2019). HiPER-V: A High Precision Radio Frequency Vehicle for Aerial Measurements. 2019 16th Annual IEEE International Conference on Sensing, Communication, and Networking (SECON). doi:10.1109/sahcn.2019.882490

    Redes Heterogéneas en el entorno vehicular

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    En la actualidad, los elementos de la infraestructura existentes para el despligue de redes vehiculares han sido desplegados en su totalidad por las operadoras de telefonía. Sin embargo, los fuertes requisitos de comunicaciones necesarios por parte de los vehículos y especialmente los vehículos autónomos, va a hacer necesario el uso combinado de las redes de telefonía (basadas en Macrocells) con otro tipo de paradigmas de red. En este artículo, presentamos un esquema para mejorar las comunicaciones vehiculares denominado DSM (\textit{Dynamic Small Cell Management}, o gestión dinámica de celdas pequeñas). La propuesta se centra en la activación dinámica de Small Cells cuando las Macrocells no son capaces de gestionar toda la información enviada por los vehículos. Para la validación de la propuesta se ha simulado un despligue real de Estaciones Base en Dublín. Los resultados de la simulación muestran mejoras en cuanto a la capacidad de comunicación y la reducción en la sobrecarga de las Estaciones Base

    International conference on the healthy effect of virgin olive oil

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    Ageing represents a great concern in developed countries because the number of people involved and the pathologies related with it, like atherosclerosis, morbus Parkinson, Alzheime's disease, vascular dementia, cognitive decline, diabetes and cancer. Epidemiological studies suggest that a Mediterranean diet (which is rich in virgin olive oil) decreases the risk of cardiovascular disease. The Mediterranean diet, rich in virgin olive oil, improves the major risk factors for cardiovascular disease, such as the lipoprotein profile, blood pressure, glucose metabolism and antithrombotic profile. Endothelial function, inflammation and oxidative stress are also positively modulated. Some of these effects are attributed to minor components of virgin olive oil. Therefore, the definition of the Mediterranean diet should include virgin olive oil. Different observational studies conducted in humans have shown that the intake of monounsaturated fat may be protective against age-related cognitive decline and Alzheimer's disease. Microconstituents from virgin olive oil are bioavailable in humans and have shown antioxidant properties and capacity to improve endothelial function. Furthermore they are also able to modify the haemostasis, showing antithrombotic properties. In countries where the populations fulfilled a typical Mediterranean diet, such as Spain, Greece and Italy, where virgin olive oil is the principal source of fat, cancer incidence rates are lower than in northern European countries. The protective effect of virgin olive oil can be most important in the first decades of life, which suggests that the dietetic benefit of virgin olive oil intake should be initiated before puberty, and maintained through life. The more recent studies consistently support that the Mediterranean diet, based in virgin olive oil, is compatible with a healthier ageing and increased longevity. However, despite the significant advances of the recent years, the final proof about the specific mechanisms and contributing role of the different components of virgin olive oil to its beneficial effects requires further investigations. © 2005 Blackwell Publishing Ltd

    Título de la cubierta: Lugo y la Revolución Gallega de 1846

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    No verso da portada: "Coleccion de trabajos políticos, sociales y económicos, dirigidos por Alejandro Armesto"Título na capa : Lugo y la Revolución Gallega de 184
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