Seismic-wave transmission across the Caribbean plate: High attenuation on concave side of Lesser Antilles Island Arc

High attenuation of short-period body waves and extremely low surface-wave group velocities have been found for seismic paths that traverse the crust and upper mantle beneath the concave side of the Lesser Antilles island arc (eastern Caribbean). The observations can be explained in terms of the currently accepted models of lithospheric plate subduction at other island arcs such as Fiji-Tonga, Marianas and the Aegean, a characteristic of which is the existence of an abnormally low Q zone in the crust and upper mantle above the down-going slab. The Greater Antilles island arc appears to be tectonically distinct, as subduction is not evident there and no anomalous low-Q zone exists south of Puerto Rico and Hispaniola. The Aves swell is probably not related tectonically to the low-Q zone, or to the subduction process, at least presently

Privacy-preserving smart metering revisited

Privacy-preserving billing protocols are useful in settings where a meter measures user consumption of some service, such as smart metering of utility consumption, pay-as-you-drive insurance and electronic toll collection. In such settings, service providers apply fine-grained tariff policies that require meters to provide a detailed account of user consumption. The protocols allow the user to pay to the service provider without revealing the user’s consumption measurements. Our contribution is twofold. First, we propose a general model where a meter can output meter readings to multiple users, and where a user receives meter readings from multiple meters. Unlike previous schemes, our model accommodates a wider variety of smart metering applications. Second, we describe a protocol based on polynomial commitments that improves the efficiency of previous protocols for tariff policies that employ splines to compute the price due

On some properties of the asymptotic Samuel function

The asymptotic Samuel function generalizes to arbitrary rings the usual order function of a regular local ring. Here we explore some natural properties in the context of excellent, equidimensional rings containing a field. In addition, we establish some results regarding the Samuel Slope of a local ring. This is an invariant related with algorithmic resolution of singularities of algebraic varieties. Among other results, we study its behavior after certain faithfully flat extensions.Comment: 21 page

Spatial distribution of stellar rotational axes from Be stars

Para conocer la distribución de velocidades de rotación de las estrellas Be, se utiliza la suposición estándar que los ejes de rotación se distribuyen uniformemente. En este trabajo usamos ángulos proyectados de polarimetría de casi 500 estrellas Be y realizamos un análisis estadístico. Además llevamos a cabo una simulación Monte Carlo cuyos resultados explican las características observadas de los ángulos, confirmando que provienen de una distribución uniforme, pero que sus ángulos proyectados poseen una estructura bimodal. Esta última característica podría cambiar las conclusiones acerca de la distribución de velocidades de rotación de estas estrellas.In order to know the distribution of rotational velocities of Be stars, a standard assumption is used, namely that the rotational axes are uniformed distributed. We use here polarimetric projected angles data from almost 500 Be stars and we make a statistical analysis. Furthermore we perform a Monte-Carlo simulation that explains the observed features of the angles, confirming that it is indeed uniform distributed, but the projected angles possess a bimodal structure. This last features may change the conclusion about the rotational velocity distribution of these stars.Fil: Curé, M.. Universidad de Valparaíso; ChileFil: Christen, A.. Universidad de Chile; ChileFil: Rivinius, Th.. European Southern Observatory; ChileFil: Rial, Diego Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigaciones Matemáticas "luis A. Santaló"; Argentina. Universidad de Valparaíso; Chil

Reduced density matrices in molecular systems: Grand-canonical electron states

Grand-canonical like descriptions of many electron atomic and molecular open systems which are characterized by a non-integer number of electrons are presented. Their associated reduced density matrices (RDMs) are obtained by introducing the contracting mapping for this type of distributions. It is shown that there is loss of information when connecting RDMs of different order by partial contractions. The energy convexity property of these systems simplifies the description. Consequently, this formulation opens the possibility to a new look for chemical descriptors such as chemical potential and reactivity among others. Examples are presented to discuss the theoretical aspects of this work.Fil: Bochicchio, Roberto Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; ArgentinaFil: Miranda Quintana, Ramón A.. Universidad de La Habana. Facultad de Química. Laboratorio de Química Computacional y Teórica; CubaFil: Rial, Diego Fernando. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Instituto de Investigaciones Matematicas

Desarrollo de una Escala de valoración radiológica del grado de Osteoartrosis para las articulaciones de la rodilla y el codo en el perro. ESCALA "BIOARTH"

La Escala Biorth es una herramienta práctica para el veterinario clínico que sirve para cuantificar los signos radiol'goicos de osteoartrosis en las articulaciones de la rodilla y el codo canino, y de esta manera

Smartphone-enabled 3D printing of medicines

3D printing is a manufacturing technique that is transforming numerous industrial sectors, particularly where it is key tool in the development and fabrication of medicinees that are personalised to the individual needs of patients. Most 3D printers are relatively large, require trained operators and must be located in a pharmaceutical setting to manufacture dosage forms. In order to realise fully the potential of point-of-care manufacturing of medicines, portable printers that are easy to operate are required. Here, we report the development of a 3D printer that operates using a mobile smartphone. The printer, operating on stereolithographic principles, uses the light from the smartphone’s screen to photopolymerise liquid resins and create solid structures. The shape of the printed dosage form is determined using a custom app on the smartphone. Warfarin-loaded Printlets (3D printed tablets) of various sizes and patient-centred shapes (caplet, triangle, diamond, square, pentagon, torus, and gyroid lattices) were successfully printed to a high resolution and with excellent dimensional precision using different photosensitive resins. The drug was present in an amorphous form, and the Printlets displayed sustained release characterises. The promising proof-of-concept results support the future potential of this compact, user-friendly and interconnected smartphone-based system for point-of-care manufacturing of personalised medications

The Geysers geothermal field: results from shear-wave splitting analysis in a fractured reservoir

Clear shear-wave splitting (SWS) is observed in 1757 high signal-to-noise ratio microearthquake seismograms recorded by two high density seismic arrays in the NW and the SE Geysers geothermal fields in California. The Geysers reservoir rocks within the study area are largely composed of lithic, low-grade metamorphism, well-fractured metagraywackes which commonly lack schistosity, warranting the general assumption that shear-wave splitting here is induced solely by stress-aligned fracturing in an otherwise isotropic medium. The high quality of observed shear-wave splitting parameters (fast shear-wave polarization directions and time delays) and the generally good data spatial coverage provide an unprecedented opportunity to demonstrate the applicability and limitations of the shear-wave splitting approach to successfully detect fracture systems in the shallow crust based on SWS field observations from a geothermal reservoir. Results from borehole stations in the NW Geysers indicate that polarization orientations range between N and N60E; while in the SE Geysers, ground surface stations show polarization directions that are generally N5E, N35E-to-N60E, N75E-to-N85E, and N20W-to-N55W. Crack orientations obtained from observed polarization orientations are in good agreement with independent field evidence, such as cracks in geological core data, tracer tests, locally mapped fractures, and the regional tectonic setting. Time delays range typically between 8 and 40 ms km, indicating crack densities well within the norm of fractured reservoirs. The sizeable collection of high resolution shear-wave splitting parameters shows evidence of prevalent vertical to nearly vertical fracture patterns in The Geysers field. At some locations, however, strong variations of SWS parameters with ray azimuth and incident angle within the shear-wave window of seismic stations indicate the presence of more complex fracture patterns in the subsurface

Producing 'Human Elements Based Medical Technologies' in Biotech Companies: Some Ethical and Organisational Ingredients for Innovative Cooking

This article is based on the findings of an EU-funded qualitative research project, entitled 'From GMP to GBP: Fostering good bioethics practices [GBP] among the European biotechnology industry', which seeks to improve the understanding of bioethical issues through the observation of the daily practices in European biotechnology companies and proposes a methodology approaching ethical issues. The comparative study was carried out in biotech companies in France, Italy, Sweden, Hungary and Belgium which develop a wide range of new technologies, all of them involving human materials or where human subjects participate (in clinical trials). Based on our findings in these local settings, we suggest that the notion of bioethics and the way its production is theorised need to be re-conceptualised. We argue that material practices and moral statements are intermingled in inextricable ways that render the formation of bioethical concerns fully dependent on the organisational landscape in which it is embedded. More precisely, the here presented co-production model of moral statements and organisational practices presents a set of common factors that influence how bioethical discourses are shaped, despite the heterogeneity of their epistemic cultures. For example, the procedural design of cell-based-products, the modes of collecting and storing biological specimen, the relationship between patients and companies and technological transfers to emerging countries are defining components that contribute to the shaping process of bioethical concerns. Thus, the path dependency of bioethical concerns relies on an already existing, specific infrastructure and existing relationships within and outside a company rather than on external judgement subsequently applied to its objects, or a collection of processes of reasoning coming from external institutions