2,444 research outputs found
Patterns of behavior in lodgings exposed to traffic noise
Threshold values for public services interferent on the attenuation to noise nuisance were defined. Daily life at home was described and collected on the use of residences, the effects of noise on health and sleep, and the incidence of running away from home. A correlation was made with the equipment and noise insulation of homes. It is shown that there are behavior patterns in the modification of considerable manner in the way of life for people who live in apartments and in individual houses, above 66 dB during daytime
A noise-immune cavity-assisted non-destructive detection for an optical lattice clock in the quantum regime
We present and implement a non-destructive detection scheme for the
transition probability readout of an optical lattice clock. The scheme relies
on a differential heterodyne measurement of the dispersive properties of
lattice-trapped atoms enhanced by a high finesse cavity. By design, this scheme
offers a 1st order rejection of the technical noise sources, an enhanced
signal-to-noise ratio, and an homogeneous atom-cavity coupling. We
theoretically show that this scheme is optimal with respect to the photon shot
noise limit. We experimentally realize this detection scheme in an operational
strontium optical lattice clock. The resolution is on the order of a few atoms
with a photon scattering rate low enough to keep the atoms trapped after
detection. This scheme opens the door to various different interrogations
protocols, which reduce the frequency instability, including atom recycling,
zero-dead time clocks with a fast repetition rate, and sub quantum projection
noise frequency stability
Definición e interpretación del derecho según Michel Villey
Michel Villey dedicó toda su fructífera vida de investigador y de
maestro a redescubrir el camino clásico, perdido entre las
fragosidades del nominalismo, de donde pretendió salir la moderna
filosofía del derecho que, con la razón humana autónoma, ha
creado monstruos con los que han querido dar vida a los caprichos
irracionales y utópicos del voluntarismo. Trató de mostrar, a la
fIlosofía contemporánea, la encrucijada a partir de la cual se podría
retornar el buen camino. Algunos lo vislumbran hoy en los valores
que hallan en las cosas, pero no acaban de reencontrarlo.
¡Dios premie al maestro!, que no sintió ningún temor en
proclamarse tomista, ¡cuando la mayor parte del clero "pasaba" de
Santo Tomas!.
El mismo me contó -hace años- que, cuando llegó a la cátedra
de historia de la filosofía del derecho de la Universidad de Paris,casi todos sus alumnos eran marxistas; pero que, a la sazón, si
bien la mitad seguían siéndolo, la otra mitad eran tomistas.
Su valentía intelectual, al ir contra la corriente de la opinión que
se exhibe y grita dogmáticamente desde los mass media, es muy
meritoria, tanto o mucho más difícil, a veces, que el valor físico. El
supo tenerla sin al baracas ni crispaciones; sino serenamente
apoyándose en datos reales y en sólidos argumentos, merecedores,
por lo menos, del mayor respeto
Tres autores de finales del XIX y principios del XX que se rebelaron contra la definición Derecho = Ley.
Demonstration of Bunch Triple Splitting in the CERN PS
A technique for splitting bunches into three has recently been proposed as an alternative to debunching-rebunching in a synchrotron[1]. The preservation of longitudinal emittance and the possibility of maintaining a gap in the bunch train are key features expected from this new process. A proof of principle has been established experimentally at the CERN PS in 1999. This showed that the nominal longitudinal characteristics of the proton beam for the LHC could be achieved at the exit of the PS with the help of triple splitting. The method is described and experimental results presented. Other possible applications are sketched
Role of the Short Distance Order in Glass Reactivity
In 2005, our group described for the first time the structural characterization at the atomic scale of bioactive glasses and the influence of the glasses’ nanostructure in their reactivity in simulated body fluids. In that study, two bioactive sol-gel glasses with composition 80%SiO2–20%CaO and 80%SiO2–17%CaO–3%P2O5 (in mol-%) were characterized by High-Resolution Transmission Electron Microscopy (HRTEM). Such characterization revealed unknown features of the glasses’ structure at the local scale that allowed the understanding of their different in vitro behaviors as a consequence of the presence or absence of P2O5. Since then, the nanostructure of numerous bioactive glasses, including melt-prepared, sol-gel derived, and mesoporous glasses, was investigated by HRTEM, Nuclear Magnetic Resonance (NMR) spectroscopy, Molecular Dynamics (MD) simulations, and other experimental techniques. These studies have shown that although glasses are amorphous solids, a certain type of short distance order, which greatly influences the in vitro and in vivo reactivity, is always present. This paper reviews the most significant advances in the understanding of bioactive glasses that took place in the last years as a result of the growing knowledge of the glasses’ nanostructure
Glasses in bone regeneration: A multiscale issue
3D scaffolds based in mesoporous bioactive glasses (MBGs) are being widely investigated to use in bone tissue engineering (TE) applications. These scaffolds are often obtained by rapid prototyping (RP) and exhibit an array of interconnected pores in a hierarchy of sizes. The ordered mesopore network (around 4 nm in diameter) is optimal for the adsorption and release of bone inductor biomolecules, and the arrangement of macropores over 100 mu m facilitates the bone cell ingrowths and angiogenesis. Nevertheless MBG composition can be varied almost infinitely at the atomic scale by including in the glass network oxides of inorganic elements with a therapeutic action. In this article the synthesis and characterization of MBG scaffolds based on the 80%SiO2-15%CaO-5%P2O5 (in mol-%) glass with substitutions up to 3.5% of Ga2O3 or Ce2O3 or 7.0% of ZnO are revisited. The substituent inclusion and the RP processing slightly decrease the surface area, the pore volume and the mesoporous order as well as their bioactive response in solutions mimicking blood plasma. However, these values still remain useful for bone TE applications. Results exhibiting the bactericide action of MBG scaffolds containing ZnO are also presented. (C) 2015 Elsevier B.V. All rights reserved
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