145 research outputs found

    SEISMO-ELECTROMAGNETIC PHENOMENA IN TECTONICALLY ACTIVE REGIONS

    Get PDF
    This work presents a research plan that aims to monitor seismo-electromagnetic signals in seismic active regions. Two effects will be considered: electromagnetic field emissions and radio broadcastings. Our study will be focused in the analysis of low magnitude earthquakes almost completely disregarded in literature. We aim to collect novel seismo-electromagnetic emission data emerging from seismic activity. We expect to address the time variation of electromagnetic properties of the crust in relation with the strain field and complement it with the development of proper models. Experimental studies based on the electrical properties of rocks will also be done aiming the understanding of pressure stimulated currents and voltages that produce detectable electromagnetic radiation and can be a cause for seismo-electromagnetic signals

    Fatty acis profile in Serra da Estrela cheese: an overview

    Get PDF
    Milk and dairy products are of major importance in the human diet, since they are an excellent source of well-balanced nutrients which are consumed in large amounts and are easy to manufacture. Most cheeses present in the market are made from cow's milk, with ewe’s and goat’s cheeses being considered delicacies derived from the unavailability of goat's and ewe’s milk in certain periods of the year, proleading to a final product with high prices that consumers tend to value given the quality of the final products. Serra Estrela (SE) cheese, a traditional variety manufactured in the center region of Portugal, is part of the national ancient cultural heritage. Made from raw sheep milk it is assumed as an iconic gourmet cheese, when compared with other Portuguese cheeses. In the present work, the evolution of the lipid fraction, namely unsaturated fatty acids such as monounsaturated and polyunsaturated (omega 3 fatty acids and omega 6 fatty acids), was evaluated for a period of 9 months. Chemically it was possible to verify differences in terms of the fatty acid profile between the analysed cheese samples. SE cheese was characterized by a relatively high content of monounsaturated fatty acids (MUFA) and the evaluation of the lipid profile of SE cheese allowed possible future work in determining bioactive lipid compounds with possible health promoting functions.info:eu-repo/semantics/publishedVersio

    Automating the processing steps for obtaining bone tissue engineered substitutes : from imaging tools to bioreactors.

    Get PDF
    Bone diseases and injuries are highly incapacitating and result in a high demand for tissue substitutes with specific biomechanical and structural features. Tissue engineering has already proven to be effective in regenerating bone tissue but has not yet been able to become an economically viable solution due to the complexity of the tissue which is very difficult to be replicated, eventually requiring the utilization of highly labour-intensive processes. Process automation is seen as the solution for mass production of cellularized bone tissue substitutes at an affordable cost by being able to reduce human intervention as well as reducing product variability. The combination of tools such as medical imaging, computer-aided fabrication and bioreactor technologies, which are currently used in tissue engineering, shows potential to generate automated production ecosystems which will in turn enable the generation of commercially available products with widespread clinical application.The authors would like to acknowledge the partial support by the European Network of Excellence EXPERTISSUES (NMP3-CT-2004-500283). Pedro Costa would also like to acknowledge the Portuguese Foundation for Science and Technology for his PhD grant (SFRH/BD/62452/2009)

    Anti-inflammatory choline based ionic liquids: Insights into their lipophilicity, solubility and toxicity parametrites

    Get PDF
    The impact on in vivo efficacy and safety of two novel ionic liquids based on the association of choline with nonsteroidal anti-inflammatory drugs, ketoprofen and naproxen forming IL-APIs, was evaluated. Their lipophilicity, solubility and toxicity were assessed aiming the illustration of the pharmaceutical profile and potential toxic impact. Partition coefficientwas determined usingmicelles of hexadecylphosphocholine and UV–Vis derivative spectroscopy. Additionally, solubility in phosphate buffer pH 7.4 wasmeasured using amodified shake flaskmethod and UV–Vis spectroscopy as detection technique. Ultimately, toxicity was considered resorting to a fully automated cytochrome c oxidase assay based onmicrofluidics. The obtained results demonstrated that the IL-APIs' drug format has the ability to interact with biological membranes and also improves solubility up to 58 times. Moreover, it was evidenced that, although being a nutrient, choline influences the IL-APIs' toxicity. The studied anti-inflammatory IL-APIs exhibited promising properties regarding their incorporation in pharmaceutical formulations

    Physics of Seismo-electromagnetic Phenomena

    Get PDF
    The seismo-electromagnetic phenomena (SEMG) are integrated in a relatively recent research field that studies diverse phenomena such as: unusual seismo-electrical signals [1], abnormal ultra-low-frequency (ULF) seismo-electromagnetic emissions [2], very-low-frequency (VLF) and low-frequency (LF) radiobroadcast anomalies associated with ionosphere perturbations [3], variation of total electron content of the ionosphere [4], and atypical infrared emissions [5], all related with the preparatory stage of impending earthquakes. In the past, like many other branches of science like Quantum Mechanics, SEMG have been responsible for intense debates about its credibility, in this case concerning its applicability to short-term earthquake prediction [6]. In fact, the development of a truly pre-quake forecasting system is still an elusive plan, but SEM emissions are now a very well established effect extensively reported in literature. Nevertheless, much of the Physics implicated is still not fully understood. Thus, our main effort is directed towards a systematic field observation of SEMG effects and the development of both constructive theoretical models and laboratorial experiments to promote a better understanding of the Physics engaged in these phenomena. In this presentation we will present a sum up of our recent achievements [7,8,9], focusing future work and improvements. [1] A. Konstantaras, et al., On the electric field transient anomaly observed at the time of the Kythira M=6.9 earthquake on January 2006, Nat. Hazards Earth Syst. Sci. 7, 677 (2007). [2] T. Bleier, et al., Investigation of ULF magnetic pulsations, air conductivity changes, and infra red signatures associated with the 30 October Alum Rock M5.4 earthquake, Nat. Hazards Earth Syst. Sci. 9, 585 (2009). [3] P. Biagi, et al., An overview on preseismic anomalies in LF radio signals revealed in Italy by wavelet analysis, Annals of Geophysics 51, 237 (2008). [4] V. Chauhan, et al., Ultra-low-frequency (ULF) and total electron content (TEC) anomalies observed at Agra and their association with regional earthquakes, Journal of Geodynamics 48, 68 (2009). [5] D. Ouzounov, et al., Outgoing long wave radiation variability from IR satellite data prior to major earthquakes, Tectonophysics 431, 211 (2007). [6] S. Uyeda, et al., Short-term earthquake prediction: Current status of seismo-electromagnetics, Tectonophysics 470, 205 (2009). [7] H.G. Silva, et al., Atmospheric electrical field anomalies associated with seismic activity, Nat. Hazards Earth Syst. Sci. 11, 987 (2011). [8] H. G. Silva, et al., Electric transport in different granitic rocks, EGU General Assembly 2011 (EGU 2011), 3-8 April 2011, Vienna (Austria). [9] H.G. Silva, et al., Piezoelectric effect during solid fracture causing electromagnetic emissions, International Conference on Computational Modelling of Fracture and Failure (CFRAC 2011), 6-8 June 2011, Barcelona (Spain)

    Update on the correlation of the highest energy cosmic rays with nearby extragalactic matter

    Get PDF
    Data collected by the Pierre Auger Observatory through 31 August 2007 showed evidence for anisotropy in the arrival directions of cosmic rays above the Greisen-Zatsepin-Kuz'min energy threshold, \nobreak{6×10196\times 10^{19}eV}. The anisotropy was measured by the fraction of arrival directions that are less than 3.13.1^\circ from the position of an active galactic nucleus within 75 Mpc (using the V\'eron-Cetty and V\'eron 12th12^{\rm th} catalog). An updated measurement of this fraction is reported here using the arrival directions of cosmic rays recorded above the same energy threshold through 31 December 2009. The number of arrival directions has increased from 27 to 69, allowing a more precise measurement. The correlating fraction is (386+7)(38^{+7}_{-6})%, compared with 2121% expected for isotropic cosmic rays. This is down from the early estimate of (6913+11)(69^{+11}_{-13})%. The enlarged set of arrival directions is examined also in relation to other populations of nearby extragalactic objects: galaxies in the 2 Microns All Sky Survey and active galactic nuclei detected in hard X-rays by the Swift Burst Alert Telescope. A celestial region around the position of the radiogalaxy Cen A has the largest excess of arrival directions relative to isotropic expectations. The 2-point autocorrelation function is shown for the enlarged set of arrival directions and compared to the isotropic expectation.Comment: Accepted for publication in Astroparticle Physics on 31 August 201
    corecore