Performance of diagnostic tests to detect respiratory viruses in older adults.

The performance of 4 laboratory methods for diagnosis of viral respiratory tract infections (RTI) in older adults was evaluated. Seventy-four nasopharyngeal (NP) swab specimens were obtained from 60 patients with RTI at a long-term care facility over 2 respiratory seasons. Sixteen specimens were positive for a respiratory virus by at least 1 method. Multiplex reverse transcriptase polymerase chain reaction (RT-PCR) by the Luminex xTAG Respiratory Viral Panel (RVP) detected 16 (100%) of the positive specimens, RVP of 24-h culture supernatant detected 8 (50%), direct fluorescent antibody testing detected 4 (25%), rapid culture detected 2 (12.5%), and rapid antigen testing detected none. For a comparison group, RVP was performed on NP swabs from 20 outpatient children with RTI. The mean fluorescence intensity by RVP was significantly lower for positive adult patients than pediatric patients (P = 0.0373). Our data suggest that older adult patients shed lower titers of viruses, necessitating a highly sensitive assay such as RT-PCR to reliably detect respiratory viral pathogens

Excitation energy transfer in light-harvesting system: Effect of initial state

The light-harvesting is a problem of long interest. It becomes active again in recent years stimulated by suggestions of quantum effects in energy transport. Recent experiments found evidence that BChla 1 and BChla 6 are the first to be excited in the Fenna-Matthews-Olson(FMO) protein, theoretical studies, however, are mostly restricted to consider the exciton in BChla 1 initially. In this paper, we study the energy transport in the FMO complex by taking different initial states into account. Optimizations are performed for the decoherence rates as to maximal transport efficiency. Dependence of the energy transfer efficiency on the initial states is given and discussed. Effects of fluctuations in the site energies and couplings are also examined.Comment: 6 pages, 6 figures, J Phys B accepte

Traffic Equations and Granular Convection

We investigate both numerically and analytically the convective instability of granular materials by two dimensional traffic equations. In the absence of vibrations the traffic equations assume two distinctive classes of fixed bed solutions with either a spatially uniform or nonuniform density profile. The former one exists only when the function V(\rho) that monitors the relaxation of grains assumes a cut off at the closed packed density, \rho_c, with V(\rho_c)=0, while the latter one exists for any form of V. Since there is little difference between the uniform and nonuniform solution deep inside the bed, the convective instability of the bulk may be studied by focusing on the stability of the uniform solution. In the presence of vibrations, we find that the uniform solution bifurcates into a bouncing solution, which then undergoes a supercritical bifurcation to the convective instability. We determine the onset of convection as a function of control parameters and confirm this picture by solving the traffic equations numerically, which reveals bouncing solutions, two convective rolls, and four convective rolls. Further, convective patterns change as the aspect ratio changes: in a vertically long container, the rolls move toward the surface, and in a horizontally long container, the rolls move toward the walls. We compare these results with those reported previously with a different continuum model by Hayakawa, Yue and Hong[Phys. Rev. Lett. 75,2328, 1995]. Finally, we also present a derivation of the traffic equations from Enskoq equation.Comment: 34 pages, 10 figure

Castration remains despite decreasing definitive treatment of localized prostate cancer in the elderly: A case for de‐implementation

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146605/1/cncr31665_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146605/2/cncr31665.pd

Density waves and 1/f1/f density fluctuations in granular flow

We simulate the granular flow in a narrow pipe with a lattice-gas automaton model. We find that the density in the system is characterized by two features. One is that spontaneous density waves propagate through the system with well-defined shapes and velocities. The other is that density waves are so distributed to make the power spectra of density fluctuations as $1/f^{\alpha}$ noise. Three important parameters make these features observable and they are energy dissipation, average density and the rougness of the pipe walls.Comment: Latex (with ps files appended

Full characterization of vibrational coherence in a porphyrin chromophore by two-dimensional electronic spectroscopy

In this work we present experimental and calculated two-dimensional electronic spectra for a 5,15-bisalkynyl porphyrin chromophore. The lowest energy electronic Qy transition couples mainly to a single 380 cm–1 vibrational mode. The two-dimensional electronic spectra reveal diagonal and cross peaks which oscillate as a function of population time. We analyze both the amplitude and phase distribution of this main vibronic transition as a function of excitation and detection frequencies. Even though Feynman diagrams provide a good indication of where the amplitude of the oscillating components are located in the excitation-detection plane, other factors also affect this distribution. Specifically, the oscillation corresponding to each Feynman diagram is expected to have a phase that is a function of excitation and detection frequencies. Therefore, the overall phase of the experimentally observed oscillation will reflect this phase dependence. Another consequence is that the overall oscillation amplitude can show interference patterns resulting from overlapping contributions from neighboring Feynman diagrams. These observations are consistently reproduced through simulations based on third order perturbation theory coupled to a spectral density described by a Brownian oscillator model

Static Friction Phenomena in Granular Materials: Coulomb Law vs. Particle Geometry

The static as well as the dynamic behaviour of granular material are determined by dynamic {\it and} static friction. There are well known methods to include static friction in molecular dynamics simulations using scarcely understood forces. We propose an Ansatz based on the geometrical shape of nonspherical particles which does not involve an explicit expression for static friction. It is shown that the simulations based on this model are close to experimental results.Comment: 11 pages, Revtex, HLRZ-33/9

Implementación de módulo de autoaprendizaje para la enseñanza de la histología del ojo y oído

La complejidad histológica de ojo y oído es un punto crítico para su aprendizaje, lo que se evidencia en los exámenes finales escritos. Para motivar su estudio y mejorar el rendimiento académico de los alumnos se implementó un Módulo de Autoaprendizaje. Se elaboró material impreso con objetivos, contenidos, metodología, cronograma de actividades y bibliografía recomendada. Presenta dos problemas (uno de ojo y otro de oído) para estimular búsqueda de información y el logro de los objetivos. Se desarrolló en 5 semanas.Facultad de Ciencias Médica

Implementación de módulo de autoaprendizaje para la enseñanza de la histología de ojo y oído

La complejidad histológica de ojo y oído es un punto crítico para su aprendizaje, lo que se evidencia en los exámenes finales escritos. Para motivar su estudio y mejorar el rendimiento académico de los alumnos se implementó un Módulo de Autoaprendizaje. Se elaboró material impreso con objetivos, contenidos, metodología, cronograma de actividades y bibliografía recomendada. Presenta dos problemas (uno de ojo y otro de oído) para estimular búsqueda de información y el logro de los objetivos. Se desarrolló en 5 semanas. El docente tuvo rol de consultor. La evaluación del aprendizaje se realizó en el examen final escrito.Facultad de Ciencias Médica

Velocity and density profiles of granular flow in channels using lattice gas automaton

We have performed two-dimensional lattice-gas-automaton simulations of granular flow between two parallel planes. We find that the velocity profiles have non-parabolic distributions while simultaneously the density profiles are non-uniform. Under non-slip boundary conditions, deviation of velocity profiles from the parabolic form of newtonian fluids is found to be characterized solely by ratio of maximal velocity at the center to the average velocity, though the ratio depends on the model parameters in a complex manner. We also find that the maximal velocity ($u_{max}$) at the center is a linear function of the driving force (g) as $u_{max} = \alpha g - \delta$ with non-zero $\delta$ in contrast with newtonian fluids. Regarding density profiles, we observe that densities near the boundaries are higher than those in the center. The width of higher densities (above the average density) relative to the channel width is a decreasing function of a variable which scales with the driving force (g), energy dissipation parameter ($\epsilon$) and the width of the system (L) as $g^{\mu} L^{\nu}/\epsilon$ with exponents $\mu = 1.4 \pm 0.1$ and $\nu = 0.5 \pm 0.1$. A phenomenological theory based on a scaling argument is presented to interpret these findings.Comment: Latex, 15 figures, to appear in PR