3,515 research outputs found
DNALinux Virtual Desktop Edition
The new version of DNALinux (VDE) is presented. DNALinux VDE is a departure from traditional distributions since it uses a virtual machine to bundle together the operating system and bioinformatics applications. The main advantage of this approach is that a virtualized environment doesn't affect a installed system. With a virtual machine a Linux system can be run under a Windows system, provided that the virtual machine player is installed. The included programs are listed and specifications to add more programs are explained. We believe that DNALinux could be used as a standardized virtual machine for learning, using, developing and testing bioinformatics applications
A 1D Model for N-level Atoms Coupled to an EM Field
We construct a model for n-level atoms coupled to quantized electromagnetic
fields in a fibrillar geometry. In the slowly varying envelope and rotating
wave approximations, the equations of motion are shown to satisfy a zero
curvature representation, implying integrability of the quantum system.Comment: 8 pages, Plain Te
Persuasion: A Case Study of Papal Influences on Fertility-Related Beliefs and Behavior
We study the persuasive impacts of non-informative communication on the short-run beliefs and long-run behavior of individuals. We do so in the context of the Papal visit to Brazil in October 1991, in which persuasive messages related to fertility were salient in Papal speeches during the visit. We use individualâs exposure to such messages to measure how persuasion shifts: (i) short-run beliefs such as intentions to contracept; (ii) long-term fertility outcomes, such as the timing and total number of births. To measure the short run causal impact of persuasion, we exploit the fact the Brazil 1991 DHS was fielded in the weeks before, during, and after the Papal visit. We use this fortuitous timing to identify that persuasion significantly reduced individual intentions to contracept by more than 40 percent relative to previsit levels, and increased the frequency of unprotected sex by 30 percent. We measure the long-run causal impacts of persuasion on fertility outcomes using later DHS surveys to conduct an event study analysis on births in a five year window either side of the 1991 Papal visit. Estimating a hazard model of fertility, we find a significant change in births nine months post-visit, corresponding to a 1.6 percent increase in the aggregate birth cohort. Our final set of results examine the very long run impact of persuasion and document the impacts to be on the timing of births rather than on total fertility
On the long time behavior of Hilbert space diffusion
Stochastic differential equations in Hilbert space as random nonlinear
modified Schroedinger equations have achieved great attention in recent years;
of particular interest is the long time behavior of their solutions. In this
note we discuss the long time behavior of the solutions of the stochastic
differential equation describing the time evolution of a free quantum particle
subject to spontaneous collapses in space. We explain why the problem is subtle
and report on a recent rigorous result, which asserts that any initial state
converges almost surely to a Gaussian state having a fixed spread both in
position and momentum.Comment: 6 pages, EPL2-Te
Potential and challenges of improving photosynthesis in algae
Sunlight energy largely exceeds the energy required by anthropic activities, and therefore its exploitation represents a major target in the field of renewable energies. The interest in the mass cultivation of green microalgae has grown in the last decades, as algal biomass could be employed to cover a significant portion of global energy demand. Advantages of microalgal vs. plant biomass production include higher lightâuse efficiency, efficient carbon capture and the valorization of marginal lands and wastewaters. Realization of this potential requires a decrease of the current production costs, which can be obtained by increasing the productivity of the most common industrial strains, by the identification of factors limiting biomass yield, and by removing bottlenecks, namely through domestication strategies aimed to fill the gap between the theoretical and real productivity of algal cultures. In particular, the lightâtoâbiomass conversion efficiency represents one of the major constraints for achieving a significant improvement of algal cell lines. This review outlines the molecular events of photosynthesis, which regulate the conversion of light into biomass, and discusses how these can be targeted to enhance productivity through mutagenesis, strain selection or genetic engineering. This review highlights the most recent results in the manipulation of the fundamental mechanisms of algal photosynthesis, which revealed that a significant yield enhancement is feasible. Moreover, metabolic engineering of microalgae, focused upon the development of renewable fuel biorefineries, has also drawn attention and resulted in efforts for enhancing productivity of oil or isoprenoids
Crystal powder statistics. I. Lorentzian line profiles in diffraction spectra of Bernoullian samples
Matrix difference equations for the supersymmetric Lie algebra sl(2,1) and the `off-shell' Bethe ansatz
Based on the rational R-matrix of the supersymmetric sl(2,1) matrix
difference equations are solved by means of a generalization of the nested
algebraic Bethe ansatz. These solutions are shown to be of highest-weight with
respect to the underlying graded Lie algebra structure.Comment: 10 pages, LaTex, references and acknowledgements added, spl(2,1) now
called sl(2,1
Local Fields without Restrictions on the Spectrum of 4-Momentum Operator and Relativistic Lindblad Equation
Quantum theory of Lorentz invariant local scalar fields without restrictions
on 4-momentum spectrum is considered. The mass spectrum may be both discrete
and continues and the square of mass as well as the energy may be positive or
negative. Such fields can exist as part of a hidden matter in the Universe if
they interact with ordinary fields very weakly. Generalization of
Kallen-Lehmann representation for propagators of these fields is found. The
considered generalized fields may violate CPT- invariance. Restrictions on
mass-spectrum of CPT-violating fields are found. Local fields that annihilate
vacuum state and violate CPT- invariance are constructed in this scope. Correct
local relativistic generalization of Lindblad equation for density matrix is
written for such fields. This generalization is particulary needed to describe
the evolution of quantum system and measurement process in a unique way.
Difficulties arising when the field annihilating the vacuum interacts with
ordinary fields are discussed.Comment: Latex 23 pages, sent to "Foundations of Physics
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