Search results for "EROD"

Phylogenetic relationships among Flavescence doree strains and related phytoplasmas determined by heteroduplex mobility assay and sequence of ribosom…

2003

Heteroduplex mobility assay (HMA) and DNA sequencing were performed on Flavescence doree (FD) phytoplasma strains and related phytoplasmas belonging to the elm yellows group. Part of the ribosomal RNA gene operon and a nonribosomal DNA region were utilized for phylogenetic analyses. Two FD strains, FD92 and FD-D, detected in France and Italy, respectively, were identical in both DNA fragments, confirming previous results. Other FD strains were all very similar and most closely resembled ALY, an Italian alder phytoplasma. Phytoplasmas associated with German Palatinate grapevine yellows were shown to form a distinct subcluster, also different from the elm yellows phytoplasma subcluster. Strai…

2020

The complex surface geometries of hailstones affect their fall behavior, fall speeds, and growth. Systematic experimental investigations on the influence of the number and length of lobes on the fall velocity and the drag coefficient of hailstones were performed in the Mainz vertical wind tunnel to provide relationships for use in numerical models. For this purpose, 3D prints of four artificial lobed hailstone models as well as spheres were used. The derived drag coefficients show no dependency in the Reynolds number in the range between 25,000 and 85,000. Further, the drag coefficients were found to increase with increasing length of lobes. All lobed hailstones show higher or similar drag …

Physical model, theoretical aspects and applications of the flight of a ball in the atmosphere. Part I: Modelling of forces and torque, and theoretic…

1991

A model of the forces and the torque operating on a ball that is flying with rotation in the atmosphere of the Earth, and the resulting system of ordinary differential equations, are derived from mechanics and aerodynamics. The system of equations allows the theoretical aspects of the flight of a ball, such as the boundedness of its kinetic energy, the curvature of the orbit or the velocity function, to be investigated using certain transformations of the variables. The solutions of the corresponding ordinary or boundary value problems, computed numerically, are used to treat certain tasks in international ball games, for example, the maximum and minimum velocities of a volleyball service.

Imaging Static Charge Distributions: A Comprehensive KPFM Theory

2018

We analyze Kelvin probe force microscopy (KPFM) for tip-sample systems that contain static charges by presenting a rigorous derivation for the respective KPFM signal in all common KPFM modes, namely amplitude modulation, frequency modulation, or heterodyne detection in the static, open-loop or closed-loop variant. The electrostatic model employed in the derivation is based on a general electrostatic analysis of an arbitrary tip-sample geometry formed by two metals, and which can include a static charge distribution and dielectric material in-between. The effect of the electrostatic force on the oscillating tip is calculated from this model within the harmonic approximation, and the observab…

Physical interpretation of laser phase dynamics

1990

The basic features characterizing the dynamical evolution of the phase of a detuned-laser field under an unstable regime are physically interpreted in terms of dispersive and dynamical effects. A general method for obtaining any attractor projection containing the phase information is established, which provides evidence for the heteroclinic character of the attractor in the presence of cavity detuning for any emission regime.

Time-Domain Integration of Terahertz pulses

2021

We report on the time-domain integration of terahertz pulses obtained via the tight confinement of the radiation in a tapered two-wire waveguide. Both simulation and experimental results prove the time integration capability of this structure.

Analysis of femtosecond Raman-induced polarization spectroscopy (RIPS) in N2 and CO2 by fitting and scaling laws

2000

Raman-induced polarization spectroscopy (RIPS) experiments were conducted at room temperature and pressures below 2 atm in pure N2 and CO2. Both homodyne and optically heterodyne detection were used. Calculations of the signal as a function of the pump–probe delay were performed taking into account the pulse duration of the laser, the rotational dependence of the dephasing rates and the small instantaneous electronic Kerr effect. The observed decay and shape of the rotational quantum beats are in good agreement with the calculations. Several sets of linewidth coefficients corresponding to the diagonal part of the collisional–rotational relaxation matrix were used. This matrix was choosen am…

Tapered Two-Wire Waveguide for Time-Domain Integration of Broadband Terahertz Pulses

2021

We show the time-domain integration of terahertz pulses achieved in a sub-wavelength, tapered two-wire waveguide. Both simulation and experimental results prove the time integration functionality of this waveguide topology.

Shape design optimization in 2D aerodynamics using Genetic Algorithms on parallel computers

1996

Publisher Summary This chapter presents two Shape Optimization problems for two dimensional airfoil designs. The first one is a reconstruction problem for an airfoil when the velocity of the flow is known on the surface of airfoil. The second problem is to minimize the shock drag of an airfoil at transonic regime. The flow is modeled by the full potential equations. The discretization of the state equation is done using the finite element method and the resulting non-linear system of equations is solved by using a multi-grid method. The non-linear minimization process corresponding to the shape optimization problems are solved by a parallel implementation of a genetic algorithm (GA). Some n…

Dumb Animals: A Short History of Classical Logocentrism

2021

Among the most common and influential stereotypes of Greco-Roman literature is the idea that animals are ‘dumb’ (ἄλογα/muta), that is, mute and devoid of reason. In recent years, several explorations of what Stephen Newmyer has aptly called the ‘man alone of animals’ topos have pointed out that in asserting the privileged status of humans the ancients attached special importance to articulate language. Yet, most of these explorations have adopted a thematic rather than historical approach in an attempt to provide a comparative assessment of ancient and modern paradigms. In the present paper, I follow a historical line through the literary representations of animals as ‘dumb’, focusing on tw…