Design of a rib impactor equipment

The human ribs must be analyzed as long and as curved bones, due to their physiology. For the development of an experimental equipment that simulate the application of loads, over the rib in the moment of a frontal collision in an automobile with seat belt, it was applied a methodology that constituted in the identification of needs and the variables which led the design of 3D model, from this it was used the technique of fused deposition modeling for the development of the equipment pieces. The supports that hold the rib ends were design with two and three degrees of freedom that allows the simulation of rib movement with the spine and the breastbone in the breathing. For the simulation of the seat belt, it was determined to applied two loads over the front part of the rib from the sagittal and lateral plane respectively, for this it was made a displacement through a lineal actuator with a speed of 4mm/s. The outcomes shown a design of an equipment able to obtain the load parameters required to generate fractures in rib specimens. The equipment may be used for the study of specimens with nearby geometries to the rib taken as a reference

Recovery and musealization of war trenches

[EN] At a time of incresing popularity of the war heritage of the province of Teruel, the coordination between different territorial administrations and the establishment of common guidelines is more necessary than ever to lead interventions in this type of sites. The work carried out in the positions of Santa Bárbara and Loma de Casares in Celadas (Teruel) are an example of how the authors understand that the conservation and enhancement of the vestiges of the Spanish Civil War should be approached, in which difficulties such as access to the position, great extension, poor workmanship and an advanced state of abandonment and deterioration converge. This work also illustrates the integral and interdisciplinary character recommended in this type of projects, which addresses the historical documentation, the interpretation of the position and the delimitation of the intervention areas, the work of archaeological excavation, the adequacy of accesses, and even signaling, promotion and tourist diffusion.[ES] En un momento en el que el patrimonio bélico de la provincia de Teruel goza de una popularidad creciente, se hace más necesario que nunca la coordinación entre las distintas administraciones territoriales y el establecimiento de unas directrices comunes que guíen las intervenciones en este tipo de enclaves. Los trabajos realizados en las posiciones de Santa Bárbara y Loma de Casares en Celadas (Teruel) son un ejemplo de cómo los autores entienden que deben abordarse la conservación y puesta en valor de los vestigios de la guerra civil española, en los que confluyen dificultades como el acceso al enclave, su gran extensión, una pobre factura y un avanzado estado de abandono y deterioro. En este trabajo también se ilustra el carácter integral e interdisciplinar que se recomienda en este tipo de proyectos, y que aborda desde la documentación histórica, la interpretación de la posición y la delimitación de las zonas de intervención, hasta las labores de excavación arqueológica, adecuación de accesos, señalización, promoción y difusión turística.García Enguita, A.; Ibáñez González, J.; Sáez Abad, R.; Villalba Alegre, I. (2023). Recuperación y musealización de trincheras de guerra. Loggia, Arquitectura & Restauración. (36):92-105. https://doi.org/10.4995/loggia.2023.19983921053

Microstructural quantification of collagen fiber orientations and its integration in constitutive modeling of the porcine carotid artery

Background Mechanical characteristics of vascular tissue may play a role in different arterial pathologies, which, amongst others, requires robust constitutive descriptions to capture the vessel wall’s anisotropic and non-linear properties.Specifically, the complex 3D network of collagen and its interaction with other structural elements has a dominating effect of arterial properties at higher stress levels.The aim of this study is to collect quantitative collagen organization as well as mechanical properties to facilitate structural constitutive models for the porcine carotid artery.This helps the understanding of the mechanics of swine carotid arteries, being a standard in clinical hypothesis testing, in endovascular preclinical trials for example. Method Porcine common carotid arteries (n = 10) were harvested and used to (i) characterize the collagen fiber organization with polarized light microscopy, and (ii) the biaxial mechanical properties by inflation testing.The collagen organization was quantified by the Bingham orientation density function (ODF), which in turn was integrated in a structural constitutive model of the vessel wall.A one-layered and thick-walled model was used to estimate mechanical constitutive parameters by least-square fitting the recorded in vitro inflation test results.Finally, uniaxial data published elsewhere were used to validate the mean collagen organization described by the Bingham ODF. Results Thick collagen fibers, i.e.the most mechanically relevant structure, in the common carotid artery are dispersed around the circumferential direction.In addition, almost all samples showed two distinct families of collagen fibers at different elevation, but not azimuthal, angles.Collagen fiber organization could be accurately represented by the Bingham ODF (¿1,2,3=[13.5,0.0,25.2] and ¿1,2,3=[14.7,0.0,26.6]; average error of about 5%), and their integration into a structural constitutive model captured the inflation characteristics of individual carotid artery samples.Specifically, only four mechanical parameters were required to reasonably (average error from 14% to 38%) cover the experimental data over a wide range of axial and circumferential stretches.However, it was critical to account for fibrilar links between thick collagen fibers.Finally, the mean Bingham ODF provide also good approximation to uniaxial experimental data. Conclusions The applied structural constitutive model, based on individually measured collagen orientation densities, was able to capture the biaxial properties of the common carotid artery. Since the model required coupling amongst thick collagen fibers, the collagen fiber orientations measured from polarized light microscopy, alone, seem to be insufficient structural information. Alternatively, a larger dispersion of collagen fiber orientations, that is likely to arise from analyzing larger wall sections, could have had a similar effect, i.e. could have avoided coupling amongst thick collagen fibers.Peer ReviewedPostprint (author's final draft

Photon statistics in collective strong coupling: Nanocavities and microcavities

There exists a growing interest in the properties of the light generated by hybrid systems involving a mesoscopic number of emitters as a means of providing macroscopic quantum light sources. In this work, the quantum correlations of the light emitted by a collection of emitters coupled to a generic optical cavity are studied theoretically using an effective Hamiltonian approach. Starting from the single-emitter level, we analyze the persistence of photon antibunching as the ensemble size increases. Not only is the photon blockade effect identifiable, but photon antibunching originated from destructive interference processes, the so-called unconventional antibunching, is also present. We study the dependence of these two types of negative correlations on the spectral detuning between cavity and emitters, as well as its evolution as the time delay between photon detections increases. Throughout this work, the performance of plasmonic nanocavities and dielectric microcavities is compared: despite the distinct energy scales and the differences introduced by their respectively open and closed character, the bunching and antibunching phenomenology presents remarkable similarities in both types of cavitiesThis work has been funded by the European Research Council under Grant Agreements No. ERC-2011-AdG 290981 and No. ERC-2016-STG-714870, the EU Seventh Framework Programme (Grants No. FP7-PEOPLE-2013-CIG-630996 and No. FP7-PEOPLE-2013-CIG-618229), and the Spanish MINECO under Contracts No. MAT2014-53432-C5-5-R and No. FIS2015-64951-R, as well as through the “María de Maeztu” programme for Units of Excellence in R&D (Grant No. MDM-2014-0377)

Organic polaritons enable local vibrations to drive long-range energy transfer

Long-range energy transfer in organic molecules has been experimentally obtained by strongly coupling their electronic excitations to a confined electromagnetic cavity mode. Here, we shed light into the polariton-mediated mechanism behind this process for different configurations: donor and acceptor molecules either intermixed or physically separated. We numerically address the phenomenon by means of Bloch-Redfield theory, which allows us to reproduce the effect of complex vibrational reservoirs characteristic of organic molecules. Our findings reveal the key role played by the middle polariton as the nonlocal intermediary in the transmission of excitations from donor to acceptor molecules. We also provide analytical insights on the key physical magnitudes that help to optimize the efficiency of the long-range energy transferThis work has been funded by the European Research Council under Grant Agreements No. ERC-2011-AdG 290981 and No. ERC- 2016-STG-714870, the EU Seventh Framework Programme (FP7-PEOPLE-2013-CIG-630996 and FP7-PEOPLE-2013- CIG-618229), and the Spanish MINECO under Contracts No. MAT2014-53432-C5-5-R and No. FIS2015-64951-R, as well as through the “María de Maeztu” programme for Units of Excellence in R&D (MDM-2014-0377)

Enhancing photon correlations through plasmonic strong coupling

© 2017 Optical Society of America. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modifications of the content of this paper are prohibitedThere is an increasing scientific and technological interest in the design and implementation of nanoscale sources of quantum light. Here, we investigate the quantum statistics of the light scattered from a plasmonic nanocavity coupled to a mesoscopic ensemble of emitters under low coherent pumping. We present an analytical description of the intensity correlations taking place in these systems and unveil the fingerprint of plasmon-exciton-polaritons in them. Our findings reveal that plasmonic cavities are able to retain and enhance excitonic nonlinearities, even when the number of emitters is large. This makes plasmonic strong coupling a promising route for generating nonclassical light beyond the single-emitter levelFP7 Ideas: European Research Council (IDEASERC) (ERC-2011-AdG 290981, ERC-2016-STG-714870, FP7-PEOPLE-2013-CIG-618229, FP7-PEOPLE-2013-CIG630996); Ministerio de Economía y Competitividad (MINECO) (FIS2015-64951-R, MAT2014-53432-C5-5-R, MDM-2014-0377

Gravitational waves from galaxy encounters

We discuss the emission of gravitational radiation produced in encounters of dark matter galactic halos. To this aim we perform a number of numerical simulations of typical galaxy mergers, computing the associated gravitational radiation waveforms as well as the energy released in the processes. Our simulations yield dimensionless gravitational wave amplitudes of the order of $10^{-13}$ and gravitational wave frequencies of the order of $10^{-16}$ Hz, when the galaxies are located at a distance of 10 Mpc. These values are of the same order as those arising in the gravitational radiation originated by strong variations of the gravitational field in the early Universe, and therefore, such gravitational waves cannot be directly observed by ground-based detectors. We discuss the feasibility of an indirect detection by means of the B-mode polarization of the Cosmic Microwave Background (CMB) induced by such waves. Our results show that the gravitational waves from encounters of dark matter galactic halos leave much too small an imprint on the CMB polarization to be actually observed with ongoing and future missions.Comment: 9 pages with revtex style, 3 ps figures; to be published in Physical Review

An unprecedented use for glycerol: chemoselective reducing agent for sulfoxides

A new application for glycerol that expands its possibilities beyond a green solvent and a precursor of value-added products has been demonstrated. Simple, easily available, and environmentally friendly dioxomolybdenum( VI) complexes are highly efficient catalysts for the chemoselective sulfoxide deoxygenation with this biomass-derived chemical feedstock. Both refined glycerol and crude glycerin can be used, thus expanding the potential application of this reaction. Subsequent transformation of glycerol during this reductive process has also been investigatedMinisterio de Ciencia e Innovacion (MICINN), FEDER (CTQ2010-15358 and CTQ2009-09949/BQU), Junta de Castilla y Leon (BU021A09 and GR-172), MICINN ("Juan de la Cierva" and "Ramon y Cajal" contracts for P.G.-G. and M.A.F.-R.

Modifications in the distribution of met-enkephalin in the cat spinal cord after administration of clonidine. An immunocytochemical study

We have studied the modifications in the distribution of methionine-enkephalin in the cat spinal cord after intravenous or intrathecal administration of clonidine by using an immunocytochemical technique. In animals not treated with the substance, a very high density of immunoreactive fibers was found in layers I and 11; a high density in the dorso-lateral funiculus and in the reticular formation; a moderate density in layers 111, IV and V; and a low density in layer VI. However, after intravenous or intrathecal administration of clonidine a decrease in fibers containing met-enkephalin was observed in layers I and I1 (high or moderate density), the dorso-lateral funiculus, and the reticular formation (moderate or low density), and in layers IV and V (low or very low density). In all cases, the decrease in the immunoreactivity was more marked when clonidine was administered intrathecally. Our results suggest that clonidine induces the release of metenkephalin in the spinal cord. They further suggest that the opioid peptide released could be involved in the control of nociceptive transmission by inhibiting the release of neurotransmitters (e.g., substance P). In summary, our study shows that clonidine could be involved in antinociceptive mechanisms in the cat spinal cord