2,920 research outputs found

    "Places making": Construcción participada de ciudades de cultura científi ca

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    In the framework of the European project Platform of Local Authorities and Communicators Engaged in Science (PLACES), we analyse the articulations between scientifi c communication, public perception of science, processes of citizen participation and apropiation of space, based on a case study of the inhabitants of Teruel city, Autonomous Community of Aragon, Spain. On the interrelationships between these issues, there are a number of contradictions, such as the difference between a high interest for information about science and technology and a low level of recognition and interaction with local institutions involved in those activities, the complex conceptualization of scientifi c space in relation to the “public-private” pair, or an articulation of a claiming civic rethoric and an insuffi cient co-responsibility. We conclude that, in a local context, the dimension of territoriality and, in particular, the identifi cation with the town, is a central mediation for activating citizen participation as part of processes of appropriation of space for setting up cities of scientifi c culture.En el marco del proyecto europeo Platform of Local Authorities and Communicators Engaged in Science (PLACES), se analizan las articulaciones entre comunicación científica, percepción pública de la ciencia, procesos de participación ciudadana y apropiación del espacio, a partir de un estudio de caso de los habitantes de la ciudad de Teruel, en la Comunidad Autónoma de Aragón, España. En las interrelaciones entre tales cuestiones, se ponen de manifiesto una serie de contradicciones, como la diferencia entre un elevado interés informativo por temas de ciencia y tecnología y un bajo nivel de reconocimiento e interacción con las instituciones locales vinculadas a aquellos, la dual y compleja conceptualización de los espacios científicos en relación con el par “público-privado”, o la coexistencia de una retórica cívica reivindicativa junto con una escasa corresponsabilidad. Se concluye que, en un contexto local, la dimensión de la territorialidad y en particular la identificación con la localidad, es una mediación central en la activación de la participación ciudadana activa como parte de procesos de apropiación del espacio para la configuración de ciudades de cultura científica

    High resolution system for nanoparticles hyperthermia efficiency evaluation

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    A system to evaluate nanoparticles efficiency in hyperthermia applications is presented. The method allows a direct measurement of the power dissipated by the nanoparticles through the determination of the first harmonic component of the in quadrature magnetic moment induced by the applied field. The magnetic moment is measured by using an induction method. To avoid errors and reduce the noise signal a double in phase demodulation technique is used. To test the system viability we have measured nanowires, nanoparticles and copper samples of different volumes to prove by comparing experimental and modeled result

    Rational stabilization of the C-LytA affinity tag by protein engineering

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    The C-LytA protein constitutes the choline-binding module of the LytA amidase from Streptococcus pneumoniae. Owing to its affinity for choline and analogs, it is regularly used as an affinity tag for the purification of proteins in a single chromatographic step. In an attempt to build a robust variant against thermal denaturation, we have engineered several salt bridges on the protein surface. All the stabilizing mutations were pooled in a single variant, C-LytAm7, which contained seven changes: Y25K, F27K, M33E, N51K, S52K, T85K and T108K. The mutant displays a 7 degrees C thermal stabilization compared with the wild-type form, together with a complete reversibility upon heating and a higher kinetic stability. Moreover, the accumulation of intermediates in the unfolding of C-LytA is virtually abolished for C-LytAm7. The differences in stability become more evident when the proteins are bound to a DEAE-cellulose affinity column, as most of wild-type C-LytA is denatured at approximately 65 degrees C, whereas C-LytAm7 may stand temperatures up to 90 degrees C. Finally, the change in the isoelectric point of C-LytAm7 enhances its solubility at acidic pHs. Therefore, C-LytAm7 behaves as an improved affinity tag and supports the engineering of surface salt bridges as an effective approach for protein stabilization

    A Proposal for a Modified Moller-Plesset Perturbation Theory

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    A modified version of the Moller-Plesset approach for obtaining the correlation energy associated to a Hartree-Fock ground state is proposed. The method is tested in a model of interacting fermions that allows for an exact solution. Using up to third order terms improved results are obtained, even more accurate in the limit of loosely bound particles. This result suggests the possible convenience of the scheme for the study of chemical bound problems.Comment: 10 pages, 1 figur

    Vaccinia-related kinase 1 (VRK1) is an upstream nucleosomal kinase required for the assembly of 53BP1 foci in response to ionizing radiation-induced DNA damage

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    Cellular responses to DNA damage require the formation of protein complexes in a highly organized fashion. The complete molecular components that participate in the sequential signaling response to DNA damage remain unknown. Here we demonstrate that vaccinia-related kinase 1 (VRK1) in resting cells plays an important role in the formation of ionizing radiationinduced foci that assemble on the 53BP1 scaffold protein during the DNA damage response. The kinase VRK1 is activated by DNA double strand breaks induced by ionizing radiation (IR) and specifically phosphorylates 53BP1 in serum-starved cells. VRK1 knockdown resulted in the defective formation of 53BP1 foci in response to IR both in number and size. This observed effect on 53BP1 foci is p53- and ataxia-telangiectasia mutated (ATM)-independent and can be rescued with VRK1 mutants resistant to siRNA. VRK1 knockdown also prevented the activating phosphorylation of ATM, CHK2, and DNA-dependent protein kinase in response to IR. VRK1 activation in response to DNA damage is a novel and early step in the signaling of mammalian DNA damage responses.This work was supported in part by Ministerio de Ciencia e Innovación Grants SAF2010-14935 and CSD2007-0017, Junta de Castilla y León Grants CSI006A11-2 and GR-15, and the Kutxa-Fundación Inbiomed. Supported by Junta para la Ampliación de Estudios-CSIC-Fondo Social Europeo fellowships.Peer Reviewe

    Continuous and Localized Mn Implantation of ZnO

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    We present results derived from continuous and localized 35 keV (55)Mn(+) ion implantations into ZnO. Localized implantations were carried out by using self-ordered alumina membranes as masks leading to ordered arrays of implanted volumes on the substrate surfaces. Defects and vacancies in the small implantation volumes of ZnO were generated due to the implantation processes besides the creation of new phases. Rapid thermal annealing was applied in the case of continuous implantation. The samples were characterized by HRSEM, GIXRD, Raman spectroscopy and RBS/C. Magnetic characterization of the samples pointed out appreciable differences among the samples obtained by the different implantation methods. This fact was mainly attributed to the different volume/surface ratios present in the implanted zones as well as to the increase of Mn atom concentrations along the grain frontiers in the nanostructured surfaces. The samples also showed a ferromagnetic transition phase at temperature value higher than room temperature

    Toward Understanding the Molecular Bases of Stretch Activation: A Structural Comparison Of The Two Troponin C Isoforms Of Lethocerus

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    Muscles are usually activated by calcium binding to the calcium sensory protein troponin-C, which is one of the three components of the troponin complex. However, in cardiac and insect flight muscle activation is also produced by mechanical stress. Little is known about the molecular bases of this calcium-independent activation. In Lethocerus, a giant water bug often used as a model system because of its large muscle fibers, there are two troponin-C isoforms, called F1 and F2, that have distinct roles in activating the muscle. It has been suggested that this can be explained either by differences in structural features or by differences in the interactions with other proteins. Here we have compared the structural and dynamic properties of the two proteins and shown how they differ. We have also mapped the interactions of the F2 isoform with peptides spanning the sequence of its natural partner, troponin-I. Our data have allowed us to build a model of the troponin complex and may eventually help in understanding the specialized function of the F1 and F2 isoforms and the molecular mechanism of stretch activation

    Regular order reductions of ordinary and delay-differential equations

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    We present a C program to compute by successive approximations the regular order reduction of a large class of ordinary differential equations, which includes evolution equations in electrodynamics and gravitation. The code may also find the regular order reduction of delay-differential equations.Comment: 4 figure

    Uso de un compuesto de fórmula (I) como bactericida frente a Streptococcus

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    Uso de al menos un compuesto de fórmula (I) donde R1 es alquilo C1-C6 o forma Ncicloalquilo C5-C8 junto con R2 ; R 2 es alquilo C1-C6, forma Ncicloalquilo C5-C8 junto con R1 , o es una cadena alquílica que se une a (CH2)n formando una amina bicíclica; R3 es alquilo C1-C2 o ausente; R4 es un sustituyente aromático que comprende al menos dos anillos aromáticos; n es un valor entre 1 y 2; y m es un valor entre 0 y 1; como bactericida frente a Streptococcus, preferiblemente frente a Streptococcus pneumoniae. Adicionalmente, compuesto de fórmula (Ia) y una composición bactericida que lo comprenda.Peer reviewedConsejo Superior de Investigaciones Científicas, Universidad Miguel HernándezB1 Patente sin examen previ
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