Limpieza real de costra negra de contaminación en arenisca silícea con láser de elevado pulso de repetición: efectos morfológicos en la superficie

This research project studies the role of pulse repetition rate in laser removal of black soiling crust from siliceous sandstone, and specifically, how laser fluence correlates with high pulse repetition rates in cleaning practice. The aim is to define practical cleaning processes and determine simple techniques for evaluation based on end-users’ perspective (restorers). Spot and surface tests were made using a Q-switched Nd:YAG laser system with a wide range of pulse repetition rates (5–200 Hz), systematically analysed and compared by macrophotography, portable microscope, stereomicroscope with 3D visualizing and area roughness measurements, SEM imaging and spectrophotometry. The results allow the conclusion that for operation under high pulse repetition rates the average of total energy applied per spot on a treated surface should be attendant upon fluence values in order to provide a systematic and accurate description of an actual laser cleaning intervention.En este trabajo se estudia el papel de la frecuencia de repetición en la limpieza láser de costras de contaminación sobre una arenisca silícea, y concretamente, como se relaciona fluencia y frecuencias elevadas en una limpieza real. Se pretende definir un procedimiento práctico de limpieza y determinar técnicas sencillas de evaluación desde el punto de vista de los usuarios finales (restauradores). Para el estudio se realizaron diferentes ensayos en spot y en superficie mediante un equipo Q-switched Nd:YAG con un amplio rango de frecuencias (5–200 Hz), que se analizaron y compararon sistemáticamente mediante macrofotografía, microscopio portátil, estereomicroscopio con visualización 3D y mediciones de rugosidad en área, imágenes SEM y espectrofotometría. Los resultados permiten proponer que, al trabajar con altas frecuencias, la media de la energía total depositada por spot en la superficie debería acompañar los valores de fluencia para describir y comprender mejor una limpieza real con láser

Antiangiogenic Therapy in Epithelial Ovarian Cancer

Approximately 75% of women with ovarian cancer are diagnosed at advanced stages (FIGO stage III/IV), with 15-23 months median global survival and 20% 5-year survival. Angiogenesis plays an important role in tumour development and proliferation. Increased angiogenesis is associated with worse clinical outcome in ovarian cancer. Here we review the play of bevacizumab in the treatment of ovarian cancer and also other antiangiogenic drugs. In total, to date there are no promising results for most of the reviewed antiangiogenic agents, except those already known for bevacizumab, trebananib, pazopanib, cediranib and nintedanib. Ongoing research will shed more light on this fascinating tumour process and its control

Papel de los equipos de atención primaria en la hospitalización infantil de los niños menores de 2 años

ObjetivoDeterminar si la conformación de los equipos de atención primaria con la realización del programa de salud del niño sano da lugar a una disminución del riesgo de hospitalización en los niños menores de 2 años, respecto al sistema sanitario tradicional de consultorio o ambulatorio.DiseñoEstudio epidemiológico de casos-referencia.Casos40% de los niños hospitalizados menores de 24 meses en plantas de hospitalización pediátricas o neonatal del Hospital Universitario Marqués de Valdecilla.Referencia15% de los recién nacidos vivos en dicho hospital. Recogida de información mediante entrevista personal y consulta de la tarjeta sanitaria.Período de estudioabril de 1995 a mayo de 1996.ResultadosLos niños menores de 2 años controlados habitualmente por un médico perteneciente a un equipo de atención primaria presentan una disminución del riesgo de hospitalización para todos los diagnósticos clínicos de 0,57 (IC del 95%, 0,35–0,93), tras haber ajustado por diferentes factores de confusión como educación materna, clase social, etnia, edad materna, consumo de tabaco materno, lactancia natural al nacimiento, ingreso al nacimiento. Se observó una disminución del riesgo de hospitalización por fiebre sin localización aparente en aquellos niños controlados habitualmente por un médico de equipo (RR ajustado, 0,41; IC del 95%, 0,19–0,90).ConclusiónLas ventajas de la reforma en la asistencia sanitaria en el ámbito pediátrico, con la conformación de los equipos de atención primaria y la realización de las actividades que ello conlleva, se traduce en una disminución del riesgo de hospitalización para aquellos niños menores de 2 años cuyo control habitual es realizado por un pediatra perteneciente a un equipo de atención primaria.ObjectiveTo determine whether the structure of primary care teams on carrying out the healthy child health programme leads to a drop in the risk of admission to hospital of children under two, in comparison with the traditional clinic or out-clinic health system.DesignCase-reference epidemiological study.Cases40% of the children under 24 months admitted to paediatric or neonate floors of the Marqués de Valdecilla University Hospital.Reference15% of the recently born children alive in this hospital. Information was gathered through face-to-face interview and by examining health cards. The study ran from April 1995 to May 1996.ResultsChildren under two monitored habitually by a doctor belonging to a primary care team showed a drop in risk of hospital admission for all clinical diagnoses of 0.57 (95% CI, 0.35–0.93), after adjustment due to various confusion factors such as maternal education, social class, ethnic background, mother's age, mother's tobacco consumption, natural breast-feeding at birth, admission at birth. There was a drop of risk of hospital admission for high temperature without apparent cause in those children monitored habitually by a team doctor (adjusted RR = 0.41; 95% CI, 0.19–0.90).ConclusionsThe advantages of the paediatric health care reform with the structuring of the primary care teams and the accompanying activities performed lead to a drop in the risk of hospital admission of those children under two years old who are habitually monitored by a doctor belonging to a primary care team

High-temperature anti-Invar behavior of gamma-Fe precipitates in Fe_xCu_(100-x) solid solutions: Ferromagnetic phases

High-temperature magnetization and neutron diffraction measurements on metastable Fe_xCu_(100-x) solid solutions have recently shown to imply that γ-Fe precipitates present ferromagnetic anti-Invar behavior. For this reason, we have studied the ferromagnetic phases of γ-Fe in moment-volume parameter space, using the general potential linearized-augmented plane-wave method and the fixed spin moment procedure in order to calculate the corresponding total energy. We find that only two ferromagnetic phases (one related to a low- spin state and the other to a high-spin state) can exist and even coexist in limited volume ranges (3.55-3.59 Å). Hence, our results provide a "revisited" version of the local spin density calculations used in the early article by Moruzzi [Phys. Rev. B 34, 1784 (1986)]. In addition, the fixed spin moment method-using an energy-moment-volume space representation-allows us to conclude that the high-spin state is the ground state of the gamma-Fe precipitates, as the anti-Invar behavior is an intrinsic property of these states. This simple scenario seems to adequately describe the perplexing phenomenology recently observed on Fe_xCu_(100-x) solid solutions

Poisson-Jacobi reduction of homogeneous tensors

The notion of homogeneous tensors is discussed. We show that there is a one-to-one correspondence between multivector fields on a manifold $M$, homogeneous with respect to a vector field $\Delta$ on $M$, and first-order polydifferential operators on a closed submanifold $N$ of codimension 1 such that $\Delta$ is transversal to $N$. This correspondence relates the Schouten-Nijenhuis bracket of multivector fields on $M$ to the Schouten-Jacobi bracket of first-order polydifferential operators on $N$ and generalizes the Poissonization of Jacobi manifolds. Actually, it can be viewed as a super-Poissonization. This procedure of passing from a homogeneous multivector field to a first-order polydifferential operator can be also understood as a sort of reduction; in the standard case -- a half of a Poisson reduction. A dual version of the above correspondence yields in particular the correspondence between $\Delta$-homogeneous symplectic structures on $M$ and contact structures on $N$.Comment: 19 pages, minor corrections, final version to appear in J. Phys. A: Math. Ge

The dependence of oxygen and nitrogen abundances on stellar mass from the CALIFA survey

We analysed the optical spectra of HII regions extracted from a sample of 350 galaxies of the CALIFA survey. We calculated total O/H abundances and, for the first time, N/O ratios using the semi-empirical routine HII-CHI-mistry, which, according to P\'erez-Montero (2014), is consistent with the direct method and reduces the uncertainty in the O/H derivation using [NII] lines owing to the dispersion in the O/H-N/O relation. Then we performed linear fittings to the abundances as a function of the de-projected galactocentric distances. The analysis of the radial distribution both for O/H and N/O in the non-interacting galaxies reveals that both average slopes are negative, but a non-negligible fraction of objects have a flat or even a positive gradient (at least 10\% for O/H and 4\% for N/O). The slopes normalised to the effective radius appear to have a slight dependence on the total stellar mass and the morphological type, as late low-mass objects tend to have flatter slopes. No clear relation is found, however, to explain the presence of inverted gradients in this sample, and there is no dependence between the average slopes and the presence of a bar. The relation between the resulting O/H and N/O linear fittings at the effective radius is much tighter (correlation coefficient $\rho_s$ = 0.80) than between O/H and N/O slopes ($\rho_s$ = 0.39) or for O/H and N/O in the individual \hii\ regions ($\rho_s$ = 0.37). These O/H and N/O values at the effective radius also correlate very tightly (less than 0.03 dex of dispersion) with total luminosity and stellar mass. The relation with other integrated properties, such as star formation rate, colour, or morphology, can be understood only in light of the found relation with mass.Comment: Accepted for publication in A&A. 20 pages, 19 figure

Magnetic nanoparticles with bulk-like properties

The magnetic behavior of $Fe_{3-x}O_4$ nanoparticles synthesized either by high-temperature decomposition of an organic iron precursor or low-temperature co-precipitation in aqueous conditions, is compared. Transmission electron microscopy, X-ray absorption spectroscopy, X-ray magnetic circular dichroism and magnetization measurements show that nanoparticles synthesized by thermal decomposition display high crystal quality and bulk-like magnetic and electronic properties, while nanoparticles synthesized by co-precipitation show much poorer crystallinity and particle-like phenomenology, including reduced magnetization, high closure fields and shifted hysteresis loops. The key role of the crystal quality is thus suggested since particle-like behavior for particles larger than about 5 nm is only observed when they are structurally defective. These conclusions are supported by Monte Carlo simulations. It is also shown that thermal decomposition is capable of producing nanoparticles that, after further stabilization in physiological conditions, are suitable for biomedical applications such as magnetic resonance imaging or bio-distribution studies.Comment: Review article. 20 pages, 7 figures. Invited contribution to 55th MMM Conference 2010 (Atlanta), Session HG-01. To be published in J. Appl. Phy

Magnetic order of Cr thin films in Nb/Cr/Fe-nanoisland hybrid: a comparative study between magnetic and superconducting properties

Shifted hysteresis loops characteristic of the exchange bias effect between a ferromagnet and an antiferromagnet are demonstrated in structures formed by a 2.5 nm Cr layer deposited on top of an array of Fe nanoislands (Cr/Fe-nanoislands). This effect evidences the persistence of antiferromagnetic (AF) order for Cr layers much thinner than the thickness reported in the literature. The field shift measured is found to increase for the smallest island sizes, which can be related with the enhancement of the Fe-nanoisland surface to volume ratio. The comparative study between superconducting proximity effects in Nb/Cr/Fe-nanoislands and Nb/normal metal/Fe-nanoisland hybrids (where the normal metals used are Al and Pt) confirms the presence of AF order in the 2.5 nm Cr spacer layer. A much shorter penetration depth of the Cooper pairs into the AF Cr layers than in the normal metal Pt and Al spacer layers is deduced

Respuesta agronómica de diferentes cultivares tintos de vid en zona templada

Se presenta la respuesta varietal de 6 cultivares tintos de vid, con riego deficitario controlado, en zona cálida: Barbera, Graciano, Mencía, Pinot noir, Petit verdot y Tempranillo. Teniendo en cuenta que en zona cálida hay que escoger cultivares de ciclo largo, recolección tardía, capaces de madurar manteniendo alta la acidez real y total, se concluye que los más idóneos para su cultivo en zona cálida son Barbera, por su alta acidez y Petit verdot y Graciano por su larga maduración y acidez equilibrada. Tempranillo, si bien en este trabajo presenta una respuesta adecuada, para equivalente maduración sacarimétrica a las anteriores posee menor acidez e IPT. Mencía madura mejor en situaciones frescas que en zona cálid

Bar pattern speeds in CALIFA galaxies: I. Fast bars across the Hubble sequence

The bar pattern speed ($\Omega_{\rm b}$) is defined as the rotational frequency of the bar, and it determines the bar dynamics. Several methods have been proposed for measuring $\Omega_{\rm b}$. The non-parametric method proposed by Tremaine \& Weinberg (1984; TW) and based on stellar kinematics is the most accurate. This method has been applied so far to 17 galaxies, most of them SB0 and SBa types. We have applied the TW method to a new sample of 15 strong and bright barred galaxies, spanning a wide range of morphological types from SB0 to SBbc. Combining our analysis with previous studies, we investigate 32 barred galaxies with their pattern speed measured by the TW method. The resulting total sample of barred galaxies allows us to study the dependence of $\Omega_{\rm b}$ on galaxy properties, such as the Hubble type. We measured $\Omega_{\rm b}$ using the TW method on the stellar velocity maps provided by the integral-field spectroscopy data from the CALIFA survey. Integral-field data solve the problems that long-slit data present when applying the TW method, resulting in the determination of more accurate $\Omega_{\rm b}$. In addition, we have also derived the ratio $\cal{R}$ of the corotation radius to the bar length of the galaxies. According to this parameter, bars can be classified as fast ($\cal{R}$ $1.4). For all the galaxies,$\cal{R}$is compatible within the errors with fast bars. We cannot rule out (at 95$\%$level) the fast bar solution for any galaxy. We have not observed any significant trend between$\cal{R}$ and the galaxy morphological type. Our results indicate that independent of the Hubble type, bars have been formed and then evolve as fast rotators. This observational result will constrain the scenarios of formation and evolution of bars proposed by numerical simulations.Comment: 17 pages, 10 figures, accepted for publication in A&