17 research outputs found
Upstream Solutions: Does the Supplemental Security Income Program Reduce Disability in the Elderly?
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72843/1/j.1468-0009.2007.00512.x.pd
PERSPECTIVAS DEL PROCESO DE GLOBALIZACIÓN Y SU INFLUENCIA SOBRE LOS DERECHOS HUMANOS ECONÓMICOS, SOCIALES Y CULTURALES
El escenario internacional se encuentra en constante transformación debido a lo que se ha denominado el proceso de “globalización”. Este afecta las relaciones internaciones interestatales e influye en la vida cotidiana de los individuos. El Derecho Internacional y más específicamente el Derecho Internacional de los Derechos Humanos no es ajeno a este proceso. La investigación afirma que nos encontramos frente a una etapa de transnacionalización de los Derechos Humanos, que permite que los individuos cuenten con mayor protección en ámbitos supranacionales. También hace especial mención a los derechos Económicos Sociales y Culturales, analiza el debate sobre el pluralismo jurídico y la eficacia diferencial. En la metodología empleada se revisan fuentes documentales y se realiza un análisis de algunos derechos particulares previstos en el Pacto de Derechos Económicos, Sociales y Culturales. Los planteamientos permiten afirmar que el proceso de globalización ha determinado la transnacionalización de los Derechos Humanos, surgiendo de dicho fenómeno consecuencias positivas y negativas en cuanto a su cumplimiento
Dynamic heterodyne near field scattering
The technique heterodyne near field scattering HNFS , originally developed for low-angle static
light scattering, has also been implemented for carrying out dynamic light scattering. While the
classical dynamic light scattering method measures the intensity-intensity correlation function,
dynamic HNFS gives directly the field-field correlation function, without any assumption on the
statistical properties of the sample, as the ones required by the Siegert relation. The technique has
been tested with calibrated Brownian particles and its performances compared to those of the
classical dynamic light scattering method
Heterodyne speckle velocimetry of Poiseuille flow
We review the technique named heterodyne speckle velocimetry and present two applications for
testing the method with a fluid moving under the conditions of Poiseuille flow. The fluid was seeded
with small tracking particles diameter 300 nm and fluxed between the two parallel planes of a cell
with constant or variable cross section. In the first case the velocity distribution was constant along
the direction parallel to the planes and was in excellent agreement with the expected Poiseuille
profile along the orthogonal direction. In the second case, where velocity gradients were present also
along the planes, the technique was able to reconstruct both the orthogonal Poiseuille profile and the
in-plane two dimensional mapping of the velocity vectors, with the possibility of measuring the fluid
flux within an accuracy of 1%
Heterodyne speckle velocimetry
We present a simple method for fluid velocimetry based on the velocity of the heterodyne speckles
generated by tracking particles illuminated with coherent light. It works in real time and provides
instantaneous two-dimensional velocity mappings in the direction orthogonal to the optical axis,
independently of the particle concentration and size, also for subwavelength particles. It also
provides the velocity distribution of the fluid over the entire sample thickness. The method has been
quantitatively tested by using the motions of rigid diffusers and applied for mapping the flow of a
confined fluid
Probing Transverse Coherence with the Heterodyne Speckle Approach: Overview and Perspectives
Confocal zero-angle dynamic depolarized light scattering
We present a novel Dynamic Depolarized Scattering method based on a tight confocal, zero
scattering angle, heterodyne scheme. The method is highly immune from parasitic multiple-scattering
contributions, so that it can operate with non-index–matched samples presenting large turbidity. It provides
measurements of both rotational and translational diffusion coefficients, the latter via number fluctuation
spectroscopy. In addition, the amplitude ratio between the two baselines for the fast rotational mode and
the slow translational mode can be used to determine the particles intrinsic birefringence
A new technique for fluid velocimetry based on near field scattering
We show that the time evolution of near-field scattering speckles, originated by a fluid suspension of particles, provides information about the velocity field in the fluid. This information can be extracted from a statistical analysis of speckle fields taken at different times, either by measuring their cross-correlation function or by recovering the power spectrum corresponding to the difference between the two speckle fields. Experimental data are in accordance to the expected behaviors. The results are independent of the scatterer's size, allowing one to exploit the technique also with sub-wavelength tracking particles
How to measure the optical thickness of scattering particles from the phase delay of scatterred waves : application to turbid samples
We present a method based on the optical theorem that yields absolute, calibration free estimates of the optical thickness of scattering particles. The thickness is determined from the phase delay of the zero angle scattered wave. It uses a heterodyne scattering scheme operating in the Raman-Nath approximation. The phase is determined by the position of Talbot-like modulations in the two dimensional power spectrum S(q(x), q(y)) of the transmitted beam intensity distribution. The method is quite insensitive to multiple scattering. It is successfully tested to provide quantitative verification of the optical theorem. Exploratory tests on soft matter samples are reported to suggest its wide applicability to turbid samples