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The Adoption and Diffusion of GM Crops in United States : A Real Option Approach
(AgBioForum, 2010)
The article aims at modelling adoption and diffusion decisions of farmers towards genetically modified crops under a real option framework. Modern GM crops help farmers to resolve two main sources of uncertainty: output ...
Economic Analysis of the Impact of Cloning on Improving Dairy Herd Composition
(AgBioForum, 2010)
While the potential for cloning animals has been realized for at least the last 25 years, it is only recently that sufficient advances have been made to allow the technology to advance to a stage where it is possible that ...
Quantum breathing mode for electrons with 1/r2 interaction
(American Physical Society, 1996)
We show that the collective excitation spectrum of electrons with 1/r2 interaction in a parabolic quantum dot of frequency ω0 contains a ''breathing'' mode of frequency 2Ω, where Ω2≡ω02+1/4ωc2 and ωc is the cyclotron ...
Edge structure of fractional quantum Hall systems from density-functional theory
(American Physical Society, 1995)
We use the Hohenberg-Kohn formulation of density-functional theory (DFT) to study the density profile at the edge of a confined two-dimensional electron gas in the fractional quantum Hall regime. The strong correlation ...
Universal equilibrium currents in the quantum Hall fluid
(American Physical Society, 1995)
The equilibrium current distribution in a quantum Hall fluid that is subjected to a slowly varying confining potential is shown to generally consist of strips or channels of current, which alternate in direction, and which ...
Center of Mass and Relative Motion in Time Dependent Density Functional Theory
(American Physical Society, 1995)
It is shown that the theorem asserting separability of the center of mass motion for a system of interacting particles in a harmonic external potential is satisfied in the time dependent density functional theory, provided ...
Rigorous upper bound for the persistent current in systems with toroidal geometry
(American Physical Society, 1995)
It is shown that the absolute value of the persistent current in a system with toroidal geometry is rigorously less than or equal to eħNα/4πmr02, where N is the number of electrons, r0-2= 〈ri-2〉 is the equilibrium average ...
Orientation of vortices in a superconducting thin film: Quantitative comparison of spin-polarized neutron reflectivity and magnetization
(American Physical Society, 2000)
We present a quantitative comparison of the magnetization measured by spin-polarized neutron reflectivity (SPNR) and dc magnetometry on a 1370 Å-thick Nb superconducting film. As a function of magnetic field applied in the ...
Optical and structural properties of ZnO films deposited on GaAs by pulsed laser deposition
(American Institute of Physics, 2000)
ZnO films were synthesized on GaAs substrates at different growth conditions by pulse laser deposition. High-purity (99.999%) oxygen was used as the ambient gas. The pressure of the ambient oxygen gas for ZnO film growth ...
Transport properties of a two-dimensional electron liquid at high magnetic fields
(American Physical Society, 2003)
The chiral Luttinger liquid model for the edge dynamics of a two-dimensional electron gas in a strong magnetic field is derived from coarse-graining and a lowest Landau level projection procedure at arbitrary filling factors ...
Solving the Ultranonlocality Problem in Time-Dependent Spin-Density-Functional Theory
(American Physical Society, 2003)
It has been known for some time that the exchange-correlation potential in time- dependent density-functional theory is an intrinsically nonlocal functional of the density as soon as one goes beyond the adiabatic approximation. ...
Collective intersubband transitions in quantum wells: A comparative density-functional study
(American Physical Society, 1998)
We use linearized time-dependent (current) density-functional theory to study collective transitions between the two lowest subbands in GaAs/AlxGa1-xAs quantum wells. We focus on two particular systems, for both of which ...
Linewidths of collective excitations of the inhomogeneous electron gas: Application to two-dimensional quantum strips
(American Physical Society, 1998)
t is well known that high-frequency collective excitations in electronic systems are not Landau damped, i.e., they cannot decay effectively into single particle-hole pairs. The leading damping mechanism in this regime is ...
Effect of disorder on the nondissipative drag between two mesoscopic metal rings
(American Physical Society, 1999)
In this paper, we consider the effect of disorder on the nondissipative Coulomb drag between two mesoscopic metal rings at zero temperature. Ring 1 has an Aharonov-Bohm flux present, which creates a persistent current J0. ...
Theory of spin Coulomb drag in spin-polarized transport
(American Physical Society, 2000)
We introduce a distinctive feature of spin-polarized transport, the spin Coulomb drag: there is an intrinsic source of friction for spin currents due to the Coulomb interaction between spin “up” and spin “down” electrons. ...
Unipolar spin diodes and transistors
(American Institute of Physics, 2000)
Unipolar devices constructed from ferromagnetic semiconducting materials with variable magnetization direction are shown theoretically to behave very similarly to nonmagnetic bipolar devices such as the p-n diode and the ...
Engineering superfluidity in electron-hole double layers
(American Physical Society, 1998)
We show that band-structure effects are likely to prevent superfluidity in semiconductor electron-hole double-layer systems. We suggest the possibility that superfluidity could be realized by the application of uniaxial ...
Stakeholder Positions Toward GM Food : the Case of Vitamin A Biofortified Cassava in Brazil
(AgBioForum, 2009)
This article examines the factors that affect stakeholders' positions toward genetically modified (GM) crops in Brazil, both in general and in the case of GM cassava in particular. Perceptions about the benefits of ...
Perceived Consequences of Herbicide-Tolerant and Insect-Resistant Crops on Integrated Pest Management Strategies in the Western United States : Results of an Online Survey
(AgBioForum, 2009)
We conducted an online survey to assess the potential effects of herbicide-tolerant (HT) and insect-resistant (IR) crops on integrated pest management (IPM) practices in the Western United States For HT crops, participants ...
The Measurement of the Light Deflection from Jupiter: Theoretical Interpretation
(arXiv, 2003)
Equations of light, propagating from quasar to observer on earth, are integrated in the time-dependent gravitational field of the solar system by making use of either retarded or advanced solutions of the Einstein field ...