1,143 research outputs found
Silodosina en el tratamiento de los síntomas del tracto urinario inferior en el varón por hiperplasia benigna de próstata: enfoque estándar y uso en la «vida real»
ResumenLos síntomas del tracto urinario inferior (STUI) son muy frecuentes en los varones, sobre todo en los mayores de 65 años. La hiperplasia benigna de próstata (HBP) es la enfermedad del varón que más se asocia a los STUI, y es una causa frecuente de alteración en la calidad de vida. Los alfabloqueantes en monoterapia representan el tratamiento de primera elección en pacientes con STUI moderados-severos secundarios a HBP.Silodosina actualmente es el alfabloqueante más uroselectivo sobre los receptores α1A, uroselectividad que ha sido confirmada en diversos estudios tanto in vitro como in vivo. En este trabajo se analizan los principales beneficios de la silodosina, tanto en los ensayos clínicos fase iii (enfoque estándar) como en la «vida real» (analizando el estudio «Silodosin in Real-life Evaluation [SiRE]», estudio de fase iv), para validar los datos de los ensayos de registro, y confirmar el perfil de riesgo-beneficio positivo de silodosina en un entorno que pueda reflejar más estrechamente la práctica clínica.AbstractLower urinary tract symptoms (LUTS) are very frequent in men, especially in those above 65 years of age. Benign prostatic hyperplasia (BPH) is the pathology most associated with LUTS in men and is a frequent cause of altered quality of life. Monotherapy with alpha blockers is the treatment of choice in patients with moderate-to-severe LUTS secondary to BPH.Silodosin is currently the most uroselective alpha blocker acting on the α1A receptors. Its uroselectivity has been confirmed in different in vitro, as well as in vivo, studies. The present study analyzed the main benefits of silodosin in phase iii clinical trials (standard approach) and in «real life» (analyzing the «Silodosin in Real-life Evaluation (SiRE)» phase iv trial) to validate the registrational trials and confirm the positive risk-benefit profile of silodosin in an environment that can more closely reflect clinical practice
The Frequency Distribution of Semi-major Axis of Wide Binaries. Cosmogony and Dynamical Evolution
The frequency distribution f(a) of semi-major axis of double and multiple
systems, as well as their eccentricities and mass ratios, contain valuable
fossil information about the process of star formation and the dynamical
history of the systems. In order to advance in the understanding of these
questions, we have made an extensive analysis of the frequency distribution f
(a) for wide binaries (a>25 AU) in the various published catalogues, as well as
in our own (Poveda et al., 1994; Allen et al., 2000; Poveda & Hernandez, 2003).
Based upon all these studies we have established that the frequency f(a) is
function of the age of the system and follows Oepik's distribution f(a) ~ 1/a
in the range of 100 AU < a < a[c](t), where a[c](t) is a critical semi-major
axis beyond which binaries have dissociated by encounters with massive objects.
We argue that the physics behind the distribution f(a) ~ 1/a is a process of
energy relaxation, analogous to that present in stellar clusters (secular
relaxation) or in spherical galaxies (violent relaxation). The frequency
distribution of mass ratios in triple systems as well as the existence of
runaway stars, indicate that both types of relaxation are important in the
process of binary and multiple star formation.Comment: International Astronomical Union. Symposium no. 240, held 22-25
August, 2006 in Prague, Czech Republi
Combined beach - inner shelf erosion in short and medium term (Maspalomas, Canary Islands)
The analysis of the accurate topo-bathymetric digital elevation model (DEM), the cartography of the submarine sedimentary cover and the monitoring of short (seasonal) and medium-term (2000-2009) morphological changes have permitted depicting the erosional trend in the short and medium-term of the Maspalomas sedimentary system. Short-term analysis showed intense sedimentary fluxes between the beaches and the inner shelf, and sedimentary exchanges with other sectors of the inner shelf, while the steep slope inner shelf fronting La Bajeta cape was identified as a sink area. In the medium-term the sediment budget showed high erosion of the supratidal and intertidal sectors of the beaches due to storm waves in the 2005-2006 winter, followed by accretion over the next four years, but which did not reach the initial sedimentary state. The inner shelf and subtidal sector of the beaches showed negative budgets in the short and medium-term. Interannual variability of the wave and wind regimes determines decadal beach erosion-accretion cycles, while long-term climatic change, evidenced at the study area by a decrease of trade winds and NE wave intensity in 2005, is expected to produce a possible increase of erosion at the El Inglés inner shelf and consequently a decrease in sediment inputs to the El Inglés beach and Maspalomas dune field. Finally, the influence of the geological heritage is depicted by the Fataga gully’s control of the present coastal morphology, and by the island relief control of the wind, waves and current directions in the study area
Uhlmann phase as a topological measure for one-dimensional fermion systems
We introduce the Uhlmann geometric phase as a tool to characterize symmetry-protected topological phases in one-dimensional fermion systems, such as topological insulators and superconductors. Since this phase is formulated for general mixed quantum states, it provides a way to extend topological properties to finite temperature situations. We illustrate these ideas with some paradigmatic models and find that there exists a critical temperature Tc at which the Uhlmann phase goes discontinuously and abruptly to zero. This stands as a borderline between two different topological phases as a function of the temperature. Furthermore, at small temperatures we recover the usual notion of topological phase in fermion systems
Screening of herbicides in grain legumes: pre-emergence herbicides in faba beans
Ante la escasez de herbicidas autorizados en leguminosas, se realizaron dos ensayos en habas con 10 herbicidas elegidos por estar autorizados en otras leguminosas o en otros países. Ninguno de los productos resultó totalmente eficaz y selectivo. Algunos de los herbicidas de preemergencia autorizados en España en habas para grano resultaron menos eficaces contra las malas hierbas y produjeron mayor fitotoxicidad que otros no autorizados. Así mismo, productos autorizados en Francia resultaron fitotóxicos en nuestras condiciones. Los mejores resultados seguido de ixosaben y aclonifen. Sin embargo será necesario ajustar dosis y buscar otras alternativas, como combinaciones de productos o estrategias de control para mejorar las eficacias y la selectividad, y sobre todo elegir los productos en función de las especies de malas hierbas dominantes en cada finca.Faced with a shortage of herbicides in legumes, two trials were conducted in faba beans to evaluate 10 herbicides elected by being authorized in other legumes or in other countries. None of the product was completely effective and selective. Some of the pre-emergence herbicides authorized in Spain for grain faba beans were less effective against weeds and produced more phytotoxicity than others not authorized. Likewise, products authorized in France turned out quite phytotoxic in our conditions. The best results were obtained with metribuzin by its effective weed control and low phytotoxicity, followed by ixosaben and aclonifen. However it will be necessary to adjust dose, to look for other alternatives, such as combinations of products or control strategies to improve effectiveness and selectivity, and above all choose the products depending on the species of dominant weeds in each farm
DIAGNÓSTICO DEL CRECIMIENTO URBANO PARA LA PLANIFICACIÓN AMBIENTAL DE VILLAHERMOSA, TABASCO, MÉXICO
Urban growth of the city of Villahermosa, Tabasco, México, since the 19th, 20th and beginning of the 21st centuries has given priority to peri-urbanization and to the establishment of oil infrastructure that alters the soil and the superficial drainage, leaving out ecosystem conservation. The estimations and projections show that if the change in land use continues in the next two decades, the last conserved ecosystems will be lost, increasing the vulnerability in face of natural disasters like flooding. A diagnosis was made by analyzing historical, social and economic information; cartographic and statistical; as well as environmental and geographic, which contributed useful information to update environmental planning that facilitates a sustainable urban expansion and conservation of the last natural spaces.El crecimiento urbano de la ciudad de Villahermosa, Tabasco, México, desde el siglo XIX, XX e inicios del XXI, ha dado prioridad a la periurbanización y establecimiento de la infraestructura petrolera que altera el suelo y la red hidráulica superficial, omitiendo la conservación de los ecosistemas. Las estimaciones y proyecciones muestran que sí continúa el cambio de uso del suelo en las dos próximas décadas, se perderán los últimos ecosistemas conservados, aumentado la vulnerabilidad ante desastres naturales, tales como las inundaciones. Se realizó un diagnóstico analizando información histórica, social y económica; cartográfica y estadística; así como ambiental y geográfica, lo cual aportó información útil para actualizar la planificación ambiental que facilite una expansión urbana sostenible y conservación de los últimos espacios naturales
Effect of dipolar interactions on the magnetization of a cubic array of nanomagnets
We investigated the effect of intermolecular dipolar interactions on a cubic
3D ensemble of 5X5X4=100 nanomagnets, each with spin . We employed the
Landau-Lifshitz-Gilbert equation to solve for the magnetization curves
for several values of the damping constant , the induction sweep rate,
the lattice constant , the temperature , and the magnetic anisotropy
field . We find that the smaller the , the stronger the maximum
induction required to produce hysteresis. The shape of the hysteresis loops
also depends on the damping constant. We find further that the system
magnetizes and demagnetizes at decreasing magnetic field strengths with
decreasing sweep rates, resulting in smaller hysteresis loops. Variations of
within realistic values (1.5 nm - 2.5 nm) show that the dipolar interaction
plays an important role in the magnetic hysteresis by controlling the
relaxation process. The dependencies of and of are presented
and discussed with regard to recent experimental data on nanomagnets.
enhances the size of the hysteresis loops for external fields parallel to the
anisotropy axis, but decreases it for perpendicular external fields. Finally,
we reproduce and test an curve for a 2D-system [M. Kayali and W. Saslow,
Phys. Rev. B {\bf 70}, 174404 (2004)]. We show that its hysteretic behavior is
only weakly dependent on the shape anisotropy field and the sweep rate, but
depends sensitively upon the dipolar interactions. Although in 3D systems,
dipole-dipole interactions generally diminish the hysteresis, in 2D systems,
they strongly enhance it. For both square 2D and rectangular 3D lattices with
, dipole-dipole interactions can cause
large jumps in the magnetization.Comment: 15 pages 14 figures, submitted to Phys. Rev.
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