Real time phase-slopes calculations by correlations using FPGAs

J. Trujillo Sevilla ; M. R. Valido ; L. F. Rodríguez Ramos ; E. Boemo ; F. Rosa ; J. M. Rodríguez Ramos, “Real time phase-slopes calculations by correlations using FPGAs,” Proc. SPIE 7015, Adaptive Optics Systems, 70153B (July 11, 2008), Norbert Hubin; Claire E. Max; Peter L. Wizinowich , 7015 (Issue) 70153B, (2008). Copyright © 2008 SPIE Society of Photo‑Optical Instrumentation Engineers. 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 modification of the content of the paper are prohibited.ELT laser guide star wavefront sensors are planned to handle an expected amount of data to be overwhelmingly large (1600x1600 pixels at 700 fps). According to the calculations involved, the solutions must consider to run on specialized hardware as Graphical Processing Units (GPUs) or Field Programmable Gate Arrays (FPGAs), among others. In the case of a Shack-Hartmann wavefront sensor is finally selected, the wavefront slopes can be computed using centroid or correlation algorithms. Most of the developments are designed using centroid algorithms, but precision ought to be taken in account too, and then correlation algorithms are really competitive. This paper presents an FPGA-based wavefront slope implementation, capable of handling the sensor output stream in a massively parallel approach, using a correlation algorithm previously tested and compared to the centroid algorithm. Time processing results are shown, and they demonstrate the ability of the FPGA integer arithmetic in the resolution of AO problems. The selected architecture is based in today’s commercially available FPGAs which have a very limited amount of internal memory. This limits the dimensions used in our implementation, but this also means that there is a lot of margin to move real-time algorithms from the conventionalThis work has been partially supported by “Programa Nacional de Diseño y Producción Industrial" (Project DPI 2006- 07906) of the “Ministerio de Educación y Ciencia" of the Spanish Government, and by “European Regional Development Fund" (ERDF)

PROCEDIMIENTO DE ENFERMERÍA: "CURAS DE HERIDAS AGUDAS Y CRÓNICAS CON EL FILETE DE ALOE VERA"

Aloe Vera, especially The Canarian variety, is a plant that has been known for thousands of years for its enormous healing properties. Throughout time there have been many testimonials to its healing powers. Aloe Vera´s miraculous healing powers originate from its two hundred active substances. Including vitamins, minerals, aminoacids, polysaccharides, enzymes, etc. The synergy of these components produces results impossible to obtain from other known treatments. Given its curative,anti inflammatory,analgesic and debridement qualities some of the nurses at the Public Health Centre in Vecindario,have been using the Aloe Vera plant to cure acute and chronicle wounds for several years now. The good results obtained,the low costs of the treatment and the approval of both patients and nurs-ing staff,justifies the continued and amplified use of Aloe Vera as an option in treatment. For this reason we are doing a comprehensive study of the Spanish bibliography so that all relative criteria can be unified.El aloe vera, en especial la variedad canaria, es una planta milenaria conocida desde la antigüedad por sus grandes propiedades curativas siendo muchísimas las citas que así lo avalan. El poder ‘milagroso’ del aloe radica en las 200 sustancias activas que contiene, entre las que se incluyen vitaminas, minerales, aminoácidos, polisacáridos, enzimas, etc. La sinergia entre todos estos componentes produce efectos imposibles de igualar por otros tratamientos conocidos. Dado el poder cicatrizante, antiinflamatorio, analgésico y desbridante, algunas enfermeras del Centro de Salud de Vecindario hacemos curas de heridas agudas y crónicas con la planta de aloe vera desde hace varios años. Los buenos resultados obtenidos, el bajo coste del tratamiento y la buena aceptación de los usuarios y las enfermeras justifican la necesidad de hacer un procedimiento de enfermería para las curas con aloe vera como una herramienta útil de trabajo (ya que hemos observado diferentes formas de uso del aloe, tanto en enfermería como en la población). Para ello hacemos una revisión exhaustiva de la bibliografía en español y de esta manera unificar criterios

Balancing porosity and mechanical properties of titanium samples to favor cellular growth against bacteria

Two main problems limit the success of titanium implants: bacterial infection, which restricts their osseointegration capacity; and the stiffness mismatch between the implant and the host cortical bone, which promotes bone resorption and risk of fracture. Porosity incorporation may reduce this difference in stiffness but compromise biomechanical behavior. In this work, the relationship between the microstructure (content, size, and shape of pores) and the antibacterial and cellular behavior of samples fabricated by the space-holder technique (50 vol % NH4HCO3 and three ranges of particle sizes) is established. Results are discussed in terms of the best biomechanical properties and biofunctional activity balance (cell biocompatibility and antibacterial behavior). All substrates achieved suitable cell biocompatibility of premioblast and osteoblast in adhesion and proliferation processes. It is worth to highlighting that samples fabricated with the 100–200 μm space-holder present better mechanical behavior—in terms of stiffness, microhardness, and yield strength—which make them a very suitable material to replace cortical bone tissues. Those results exposed the relationship between the surface properties and the race of bacteria and mammalian cells for the surface with the aim to promote cellular growth over bacteria.University of Seville (Spain) VI Plan Propio de Investigación y Transferencia—US 2018, I.3A

Estimating the longitudinal magnetic field in the chromosphere of quiet-Sun magnetic concentrations

Details of the magnetic field in the quiet Sun chromosphere are key to our understanding of essential aspects of the solar atmosphere. We aim to determine the longitudinal magnetic field component (B_lon) of quiet Sun regions depending on their size. We estimated B_lon by applying the weak-field approximation (WFA) to high-spatial-resolution Ca II 854.2 nm data taken with the Swedish 1m Solar Telescope. Specifically, we analyzed the estimates inferred for different spectral ranges using the data at the original cadence and temporally integrated signals. The longitudinal magnetic field in each considered plasma structure correlates with its size. Using a spectral range restricted to the line core leads to chromospheric longitudinal fields varying from 50 G at the edges to 150-500 G at the center of the structure. These values increase as the spectral range widens due to the photospheric contribution. However, the difference between this contribution and the chromospheric one is not uniform for all structures. Small and medium-sized concentrations show a steeper height gradient in B_lon compared to their chromospheric values, so estimates for wider ranges are less trustworthy. Signal addition does not alleviate this situation as the height gradients in B_lon are consistent with time. Finally, despite the amplified noise levels that deconvolving processes may cause, data restored with the destretching technique show similar results, though are affected by smearing. We obtained B_lon estimates similar to those previously found, except for large concentrations and wide spectral ranges. In addition, we report a correlation between the height variation of B_lon compared to the chromospheric estimates and the concentration size. This correlation affects the difference between the photospheric and chromospheric magnetic flux values and the reliability of the estimates for wider spectral ranges.Comment: 14 pages, 14 figures. Accepted for publication in Astronomy & Astrophysics; abstract has been abridge

Non-local thermodynamic equilibrium inversions from a 3D MHD chromospheric model

The structure of the solar chromosphere is believed to be governed by magnetic fields, even in quiet-Sun regions that have a relatively weak photospheric field. During the past decade inversion methods have emerged as powerful tools for analyzing the chromosphere of active regions. The applicability of inversions to infer the stratification of the physical conditions in a dynamic 3D solar chromosphere has not yet been studied in detail. This study aims to establish the diagnostic capabilities of non-local thermodynamical equilibrium (NLTE) inversion techniques of Stokes profiles induced by the Zeeman effect in the Ca II 8542 line. We computed the Ca II atomic level populations in a snapshot from a 3D radiation-MHD simulation of the quiet solar atmosphere in non-LTE using the 3D radiative transfer code Multi3d. These populations were used to compute synthetic full-Stokes profiles in the Ca II 8542 line using 1.5D radiative transfer and the inversion code Nicole. The profiles were then spectrally degraded to account for finite filter width and Gaussian noise was added to account for finite photon flux. These profiles were inverted using Nicole and the results were compared with the original model atmosphere. Our NLTE inversions applied to quiet-Sun synthetic observations provide reasonably good estimates of the chromospheric magnetic field, line-of-sight velocities and somewhat less accurate, but still very useful, estimates of the temperature. Three dimensional scattering of photons cause cool pockets in the chromosphere to be invisible in the line profile and consequently they are also not recovered by the inversions. To successfully detect Stokes linear polarization in this quiet snapshot, a noise level below 10^{-3.5} is necessary.Comment: Accepted for publication in Astronomy & Astrophysic

Porous Titanium surfaces to control bacteria growth: mechanical properties and sulfonated polyetheretherketone coating as antibiofounling approaches

Here, titanium porous substrates were fabricated by a space holder technique. The relationship between microstructural characteristics (pore equivalent diameter, mean free-path between pores, roughness and contact surface), mechanical properties (Young’s modulus, yield strength and dynamic micro-hardness) and bacterial behavior are discussed. The bacterial strains evaluated are often found on dental implants: Methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa. The colony-forming units increased with the size of the spacer for both types of studied strains. An antibiofouling synthetic coating based on a sulfonated polyetheretherketone polymer revealed an effective chemical surface modification for inhibiting MRSA adhesion and growth. These findings collectively suggest that porous titanium implants designed with a pore size of 100–200 µm can be considered most suitable, assuring the best biomechanical and bifunctional anti-bacterial properties.University of Seville VI Plan Propio de Investigación y Transferencia—US 2018, I.3A

Optimización de ataques a redes complejas mediante un algoritmo de colonias de abejas artificiales

En los últimos años, ha crecido el interés en formular como un problema de optimización la tarea de concebir ataques efectivos que causen el máximo daño sobre redes complejas. En este caso, los ataques se modelan como un proceso de eliminación de k vértices del grafo que representa la red. En este trabajo, seguimos esta línea de investigación presentando un problema de optimización que concierne la selección de los nodos a eliminar con el objetivo de minimizar el máximo valor de intermediación en el grafo residual. La intermediación es una medida de centralidad bien conocida que evalúa la importancia de los nodos de la red de acuerdo a su participación en los caminos más cortos. La relevancia de este indicador dentro de la tecnología actual disponible para el análisis de redes nos ha llevado a plantear esta técnica para planificar ataques efectivos sobre redes. Además, para abordar el problema de optimización, proponemos un algoritmo de colonias de abejas artificiales, que es una técnica de inteligencia colectiva inspirada en el comportamiento de las abejas cuando realizan la búsqueda de comida. Nuestra propuesta explota el conocimiento útil sobre el problema que se obtiene de la exploración de las fuentes de comida, aplicando una destrucción parcial de las soluciones escogidas y una reconstrucción heurística de las mismas. Mediante el análisis experimental de los resultados mostramos el buen comportamiento del algoritmo propuesto, con respecto a métodos de la literatura que pueden adoptarse para enfrentarse con el problema, tal como el método de ataque secuencial basado en centralidad

Cocirculation and Coinfection Associated to Zika Virus in the Americas

Zika virus, a flavivirus, has arrived to Latin America in 2013. It became evident causing epidemics since 2015, first in Brazil and later in other countries in the region, such as Colombia, with a higher peak in 2016. The World Health Organization (WHO), based on cumulated evidence on its association with Guillain-Barre syndrome (GBS) and microcephaly and other birth defects (also the congenital Zika syndrome, CZS), declared for a period of almost a year, an international public health emergency. Epidemics in the region caused around 1 million cases with also additional complications beyond GBS and the CZS, which in patients with comorbidities lead to deaths. Among the events studied in the region, a number of cases with arboviral coinfections/codetection (dengue and chikungunya) were described and published beginning in Colombia and later in Brazil. In addition to that, cocirculation and still ongoing research on antibody-dependent enhancement (ADE) are challenges for physicians and public health authorities, given the implications for clinical manifestations and serological diagnosis in patients with previous exposition to other flaviviruses. We reviewed such aspects in this chapter