90 research outputs found
N-representability and stationarity in time-dependent density functional theory
To construct an N-representable time-dependent density-functional theory, a
generalization to the time domain of the Levy-Lieb (LL) constrained search
algorithm is required. That the action is only stationary in the Dirac-Frenkel
variational principle eliminates the possibility of basing the search on the
action itself. Instead, we use the norm of the partial functional derivative of
the action in the Hilbert space of the wave functions in place of the energy of
the LL search. The electron densities entering the formalism are
-representable, and the resulting universal action functional has a unique
stationary point in the density at that corresponding to the solution of the
Schr\"{o}dinger equation. The original Runge-Gross (RG) formulation is subsumed
within the new formalism. Concerns in the literature about the meaning of the
functional derivatives and the internal consistency of the RG formulation are
allayed by clarifying the nature of the functional derivatives entering the
formalism.Comment: 9 pages, 0 figures, Phys. Rev. A accepted. Introduction was expanded,
subsections reorganized, appendix and new references adde
Local Isoelectronic Reactivity of Solid Surfaces
The quantity w^N(r) = ( 1/ k^2 T_el)[partial n(r, T_el) / partial
T_el]_(v(r),N) is introduced as a convenient measure of the local isoelectronic
reactivity of surfaces. It characterizes the local polarizability of the
surface and it can be calculated easily. The quantity w^N(r) supplements the
charge transfer reactivity measured e.g. by the local softness to which it is
closely related. We demonstrate the applicability and virtues of the function
w^N(r) for the example of hydrogen dissociation and adsorption on Pd(100).Comment: RevTeX, 13 pages, 3 figures, to appear in Phys. Rev. Let
A simplified microwave-based motion detector for home cage activity monitoring in mice
Background: Locomotor activity of rodents is an important readout to assess well-being and physical health, and is pivotal for behavioral phenotyping. Measuring homecage-activity with standard and cost-effective optical methods in mice has become difficult, as modern housing conditions (e.g. individually ventilated cages, cage enrichment) do not allow constant, unobstructed, visual access. Resolving this issue either makes greater investments necessary, especially if several experiments will be run in parallel, or is at the animals' expense. The purpose of this study is to provide an easy, yet satisfying solution for the behavioral biologist at novice makers level. Results: We show the design, construction and validation of a simplified, low-cost, radar-based motion detector for home cage activity monitoring in mice. In addition we demonstrate that mice which have been selectively bred for low levels of anxiety-related behavior (LAB) have deficits in circadian photoentrainment compared to CD1 control animals. Conclusion: In this study we have demonstrated that our proposed low-cost microwave-based motion detector is well-suited for the study of circadian rhythms in mice
A genetically optimized level set approach to segmentation of thyroid ultrasound images
Menstrual cycle worsening of epileptic seizures in women with symptomatic focal epilepsy
A simplified microwave-based motion detector for home cage activity monitoring in mice
TGF beta and IL13 in schistosomiasis mansoni associated pulmonary arterial hypertension; a descriptive study with comparative groups
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