426 research outputs found

    From paper maps to the Digital Earth and the Internet of Places

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    Maps have always been tools that have fascinated men, for their ability to make us see the world that surrounds us. They were and are the outcome of models and methods applied to the observation of the world, starting from geodesy, surveying photogrammetry and remote sensing. All these disciplines, which we now group under the new name of geomatics, have had a tremendous boost in recent years. However, the synergy with information computer technology is probably the aspect that is revolutionizing more cartography. Earlier computers and after the Internet have brought us to new concepts and tools that will have profound effects not only in the world of niche of cartographers, but also more generally in the life of all human beings. The Digital Earth, proposed in 1998 by Al Gore, has been enriched in just twenty years of a set of new demands, which make even more interesting and challenging being cartographers today. The paper, without claiming to be comprehensive, aims at providing a concise overview of the state of art and of the advancement in this area. Moreover, it urges the community of geomatics to be protagonist and promoter of a new cartography, largely to be reinvented, and that would put us at the center of processes of knowledge and management of the Earth. The map makers in the past helped discovering new worlds, now the challenge is to rediscover our common world with new eyes of environmental, social, economic equity, sustainability and participation

    Nanotechnology and the diagnosis/treatment of leishmaniasis

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    Aim: The review article updates the current state of the art in the engineering of nanoplatforms against leishmaniasis. Special attention is devoted to the development of drug nanocarriers to be given to patients through the parenteral, topical, and oral routes of administration. Challenges and opportunities coming from advanced formulation methods/strategies introduced in the design of these nanosystems are emphasized. Finally, particular attention is also given to the use of nanoparticulate systems for vaccine delivery and for the diagnosis of the disease. Materials and Methods: To that aim, the Web sites of PubMed, HCAplus, Thomson, and Registry were used as the main sources to perform the search for the most significant research articles published on the subject. The information was then carefully analyzed, highlighting the most important preclinical results in the development of nanomedicines against leishmaniasis, as well considering vaccine delivery systems and nanoparticulate-based diagnosis. Results and Conclusion: The introduction of nanotechnology into the leishmaniasis arena is intended to optimize both the diagnosis and treatment (drug/vaccine therapy) of the disease. The objective is always to improve the selectivity of the imaging molecules or drugs/vaccines toward the parasite, especially when it is located inside phagocytic cells and neutrophils, while keeping to a very minimum the toxic side effects. Of course, only the wise engineering of the nanoparticulate delivery system will assure the best diagnostic/therapeutic outcomes.Objetivos: Este trabajo pretende actualizar la situación actual en el diseño de nanoplataformas contra la leishmaniasis. En este sentido, especial atención merecen los nanotransportadores de fármacos diseñados para ser administrados al paciente a través de las vías de administración parenteral, tópica y oral. Asimismo, se discuten las posibilidades que ofrecen las técnicas o estrategias de formulación más avanzadas en el diseño de estas nanoplataformas biomédicas. Finalmente, también se dedica especial atención a la utilización de estos nanosistemas en la administración de vacunas y en el diagnóstico de la leishmaniasis. Material y Métodos: Con este fin, se utilizaron las páginas Web PubMed, HCAplus, Thomson y Registry como principales fuentes para la búsqueda de los trabajos de investigación más interesantes publicados sobre la materia. La información así obtenida fue cuidadosamente analizada, resaltando aquellos resultados preclínicos más relevantes en cuanto al desarrollo de nanomedicamentos contra la leishmaniasis, y considerando también los nanosistemas transportadores de vacunas y las nanoplataformas de utilidad en el diagnóstico de esta enfermedad. Resultados y conclusiones: La nanotecnología es utilizada para mejorar el diagnóstico y tratamiento de la leishmaniasis. El objetivo es, en todos los casos, la mejora de la selectividad por el parásito de los fármacos, vacunas y moléculas utilizadas como agentes de contraste en técnicas de imagen, especialmente cuando este microorganismo se encuentra localizado en el interior de macrófagos y neutrófilos. Con esta interesante nanoherramienta, se puede también obtener una significativa reducción en la aparición y severidad de la toxicidad asociada a las técnicas de diagnóstico y tratamiento de la leishmaniasis. Es evidente que sólo con un inteligente diseño de estos nanosistemas se logran los mejores resultados de diagnóstico y terapia de la enfermedad

    Ultrasmall superparamagnetic iron oxide particles for biomedical applications

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    Las partículas superparamagnéticas ultrapequeñas de óxido de hierro (USPIO) tienen una enorme utilidad en Biomedicina como agentes de contraste en resonancia magnética de imagen o como sistemas transportadores de fármacos, entre otras aplicaciones. La naturaleza del recubrimiento de los núcleos inorgánicos de las partículas USPIO determina su estabilidad in vitro y su comportamiento in vivo, siendo especialmente importantes sus propiedades fi sicoquímicas, en concreto el tamaño, la carga superfi cial y la densidad del recubrimiento. Las pequeñas dimensiones de las partículas USPIO hace difícil una caracterización fi sicoquímica completa, la cuál es de suma importancia para poder mejorar su estabilidad y comportamiento in vivo. Esta revisión se centra en las técnicas instrumentales utilizadas en el análisis de los núcleos magnéticos y de sus recubrimientos orgánicos.Ultrasmall superparamagnetic iron oxide (USPIO) particles are iron oxide nanoparticles currently used for Biomedical applications: contrast agents in magnetic resonance imaging, drug delivery systems, etc. The coatings surrounding the USPIO inorganic core may control the in vitro stability and the in vivo fate. Different physicochemical properties such as the fi nal size, the surface charge and the density of coverage are key factors in this respect. A complete physicochemical characterization of USPIOs particles is diffi cult due to their small dimensions. However, such a characterization is necessary to improve the stability of the particles and their in vivo behaviour. This review is focused on the techniques which can be applied to have a better insight in the magnetic core structure of these particles and their organic surface

    Evaluation of the effect of training using auditory stimulation on rhythmic movement in Parkinsonian patients—a combined motor and [18F]-FDG PET study

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    [Abstract] Introduction: A programme of rehabilitation using auditory cues has previously been shown to decrease movement variability in the gait of Parkinsonian patients. Objective and methods: We studied the temporal variability of finger-tapping and gait in 9 patients with Parkinson's disease (PD) before and after they undertook a physical rehabilitation programme. Positron Emission Tomography (PET) using 2-deoxy-2[18F]fluoro-d-glucose (FDG) was performed in these subjects to look for changes in metabolic brain activity after completion of the rehabilitation program. Results: The reduction of variability was seen not only in gait but also other repetitive movements such as finger tapping. Furthermore, here we show differences in resting regional cerebral glucose utilisation in these patients compared to healthy controls (significant hypometabolism—p<0.001—for the PD group in the right parietal and temporal lobes, left temporal and frontal lobes and a hypermetabolism in the left cerebellum) and specific changes following the improvements in repetitive movement abilities (significant metabolic increment—p<0.001—in the PD group in the right cerebellum and in the right parietal and temporal lobes). Conclusions: Although our study does not allow us to draw firm conclusions, it provides new information on the neural basis of auditory stimulation in PD. Our results extend those from previous studies to show improvement in the temporal variability of two types of rhythmic movements after participation by PD patients in a physical rehabilitation programme, along with changes in glucose uptake in several brain areas involved in sensorimotor processing.Xunta de Galicia; PGIDIT02BTF13701P

    Application of the sine-cosine algorithm to the optimal design of a closed coil helical spring

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    This paper proposes the application of the sinecosine algorithm (SCA) to the optimal design of a closed coil helical spring. The optimization problem addressed corresponds to the minimization of total spring volume subject to physical constraints that represents the closed coil helical spring such as maximum working load, shear stress, and minimum diameter requirements, among other. The resulting mathematical formulation is a complex nonlinear and non-convex optimization model that is typically addressed in literature with trial and error methods or heuristic algorithms. To solve this problem efficiently, the SCA is proposed in this research. This optimization algorithm belongs to the family of the metaheuristic optimization techniques, it works with controlled random processes guided by sine and cosine trigonometric functions, that allows exploring and exploiting the solution space in order to find the best solution to the optimization problem. By presenting as main advantage an easy implementation at any programming language using sequential quadratic programming; eliminating the need to uses specialized and costly software. Numerical results demonstrating that the proposes SCA allows reaching lower spring volume values in comparison with literature approaches, such as genetic algorithms, particle swarm optimization methods, among others. All the numerical simulations have been implemented in the MATLAB software

    NOD2 Modulates Serotonin Transporter and Interacts with TLR2 and TLR4 in Intestinal Epithelial Cells

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    Background/Aims: Serotonin (5-HT) is a chief modulator of intestinal activity. The effects of 5-HT depend on its extracellular availability, which is mainly controlled by serotonin transporter (SERT), expressed in enterocytes. On the other hand, innate immunity, mediated by Toll-like receptors (TLRs) and nucleotide oligomerization domain (NOD)-like receptors (NLRs), is known to control intestinal microbiota and maintain intestinal homeostasis. The dysregulation of the intestinal serotonergic system and innate immunity has been observed in in ammatory bowel diseases (IBD), the incidence of which has severely increased all over the world. The aim of the present study, therefore, was to analyze the effect of NOD2 on intestinal SERT activity and expression, as well as to study the crosstalk of NOD2 with TLR2 and TLR4. Methods: Intestinal epithelial cell line Caco-2/TC7 was used to analyze SERT activity and SERT, NOD2, TLR2 and TLR4 molecular expression by real-time PCR and western blotting. Moreover, intestinal tract (ileum and colon) from mice de cient in TLR2, TLR4 or TLR2/4 receptors was used to test the interdependence of NOD2 with these TLR receptors. Results: NOD2 activation inhibits SERT activity in Caco-2/TC7 cells, mainly due to the decrement of SERT molecular expression, with RIP2/RICK being the intracellular pathway involved in this effect. This inhibitory effect on SERT would yield an increment of extracellular 5-HT availability. In this sense, 5-HT strongly inhibits NOD2 expression. In addition, NOD2 showed greater interdependence with TLR2 than with TLR4. Indeed, NOD2 expression signi cantly increased in both cells treated with TLR2 agonists and the intestinal tract of Tlr2-/- mice. Conclusions: It may be inferred from our data that NOD2 could play a role in intestinal pathophysiology not only through its inherent innate immune role but also due to its interaction with other receptors as TLR2 and the modulation of the intestinal serotonergic system decreasing SERT activity and expression

    Microstructural and magnetic characterization of Fe- and Ir-based multilayers

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    Nominal [Fe(t)/Ir(t'')](n) (M/Mtype), [FeOx(t)/IrOx(t'')](n) (O/O), and [Fe(t)/IrOx(t'')](n) (M/O) multilayers have been prepared by magnetron sputtering at room temperature. Composition, structure, and magnetic behavior have been analyzed. In the M/M samples, the Fe and Ir phases are identified as bcc and fcc, respectively. The magnetism evolves from bulklike iron to granular behavior as the thickness of the Fe layers decreases. An induced magnetic moment, ferromagnetically coupled to Fe, is observed on Ir by x-ray magnetic circular dichroism (XMCD). Besides, the presence of negative remanent magnetization is observed in the M/M samples. As for the M/O samples, the stronger affinity of iron for oxygen displaces the oxygen atoms giving rise to actual heterostructures that strongly differ from the nominal ones. For similar thickness of the two layers the Fe layer become oxidized while a mixture of metal and oxide phases is found in the Ir layer. The increase of the Fe thickness leads to a metallic Ir layer and a highly coercive (similar to 4.4 kOe) core-shell metal-oxide structure in the Fe layers

    Toll-like receptors 2 and 4 cooperate in the control of the emerging pathogen Brucella microti

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    Toll-like receptors (TLRs) recognize pathogen-derived molecules and play a critical role during the host innate and adaptive immune response. Brucella spp. are intracellular gram-negative bacteria including several virulent species, which cause a chronic zoonotic infection in a wide range of mammalian hosts known as brucellosis. A new Brucella species, Brucella microti, was recently isolated from wild rodents and found to be highly pathogenic in mice. Using this species-specific model, it was previously found that CD8+ T cells are required to control this infection. In order to find out the role of TLR-mediated responses in the control of this pathogen, the course of infection of B. microti was analyzed over 3 weeks in wild-type (WT) and TLR knock out (KO) mice including TLR2-/-, TLR4-/-, TLR9-/-, TLR2×4-/- and TLR2×4×9-/-. WT and single TLR2, TLR4 and TLR9 KO mice similarly control infection in liver and spleen. In contrast, bacterial clearance was delayed in TLR2×4-/- and TLR2×4×9-/- mice at 7 and 14 days post-infection. This defect correlated with impaired maturation and pro-inflammatory cytokine production in B. microti-infected dendritic cells from TLR2×4-/- and TLR2×4×9-/- mice. Finally, it was found that Tc cells from TLR2×4-/- and TLR2×4×9-/- mice showed reduced ability to inhibit growth of B. microti in macrophages, suggesting the involvement of TLR2 and 4 in the generation of specific Tc cells. Our findings indicate that TLR2 and TLR4 are required to control B. microti infection in mice and that this effect could be related to its participation in the maturation of dendritic cells and the generation of specific CD8+ Tc cells

    Microstructural and magnetic characterization of Fe- and Ir-based multilayers

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    Nominal [Fe(t)/Ir(t′)]n (M/M type), [FeOx(t)/IrOx(t′)]n (O/O), and [Fe(t)/IrOx(t′)]n (M/O) multilayers have been prepared by magnetron sputtering at room temperature. Composition, structure, and magnetic behavior have been analyzed. In the M/M samples, the Fe and Ir phases are identified as bcc and fcc, respectively. The magnetism evolves from bulklike iron to granular behavior as the thickness of the Fe layers decreases. An induced magnetic moment, ferromagnetically coupled to Fe, is observed on Ir by x-ray magnetic circular dichroism (XMCD). Besides, the presence of negative remanent magnetization is observed in the M/M samples. As for the M/O samples, the stronger affinity of iron for oxygen displaces the oxygen atoms giving rise to actual heterostructures that strongly differ from the nominal ones. For similar thickness of the two layers the Fe layer become oxidized while a mixture of metal and oxide phases is found in the Ir layer. The increase of the Fe thickness leads to a metallic Ir layer and a highly coercive (∼4.4 kOe) core-shell metal-oxide structure in the Fe layers.Spanish Ministry of Economy and Competitiveness (MINECO), MAT2014-54425-R, MAT2017-83468-RAragón DGA NETOSHIM
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