330 research outputs found
Nonlinear Schroedinger Equations within the Nelson Quantization Picture
We present a class of nonlinear Schroedinger equations (NLSEs) describing, in
the mean field approximation, systems of interacting particles. This class of
NLSEs is obtained generalizing expediently the approach proposed in Ref. [G.K.
Phys. Rev. A 55, 941 (1997)], where a classical system obeying to an
exclusion-inclusion principle is quantized using the Nelson stochastic
quantization. The new class of NLSEs is obtained starting from the most general
nonlinear classical kinetics compatible with a constant diffusion coefficient
D=\hbar/2m. Finally, in the case of s-stationary states, we propose a
transformation which linearizes the NLSEs here proposed.Comment: 5 pages, (RevTeX4), to appear in Rep. Math. Phys. 51 (2003
Evaluation of the national academy of parenting practitioners' training offer in evidence based parenting programmes
Novel Chalcone-Based Fluorescent Human Histamine H3 Receptor Ligands as Pharmacological Tools
Novel fluorescent chalcone-based ligands at human histamine H3 receptors (hH3R) have been designed, synthesized, and characterized. Compounds described are non-imidazole analogs of ciproxifan with a tetralone motif. Tetralones as chemical precursors and related fluorescent chalcones exhibit affinities at hH3R in the same concentration range like the reference antagonist ciproxifan (hH3R pKi value of 7.2). Fluorescence characterization of our novel ligands shows emission maxima about 570 nm for yellow fluorescent chalcones and ≥600 nm for the red fluorescent derivatives. Interferences to cellular autofluorescence could be excluded. All synthesized chalcone compounds could be used to visualize hH3R proteins in stably transfected HEK-293 cells using confocal laser scanning fluorescence microscopy. These novel fluorescent ligands possess high potential to be used as pharmacological tools for hH3R visualization in different tissues
Classical kinetic energy, quantum fluctuation terms and kinetic-energy functionals
We employ a recently formulated dequantization procedure to obtain an exact
expression for the kinetic energy which is applicable to all kinetic-energy
functionals. We express the kinetic energy of an N-electron system as the sum
of an N-electron classical kinetic energy and an N-electron purely quantum
kinetic energy arising from the quantum fluctuations that turn the classical
momentum into the quantum momentum. This leads to an interesting analogy with
Nelson's stochastic approach to quantum mechanics, which we use to conceptually
clarify the physical nature of part of the kinetic-energy functional in terms
of statistical fluctuations and in direct correspondence with Fisher
Information Theory. We show that the N-electron purely quantum kinetic energy
can be written as the sum of the (one-electron) Weizsacker term and an
(N-1)-electron kinetic correlation term. We further show that the Weizsacker
term results from local fluctuations while the kinetic correlation term results
from the nonlocal fluctuations. For one-electron orbitals (where kinetic
correlation is neglected) we obtain an exact (albeit impractical) expression
for the noninteracting kinetic energy as the sum of the classical kinetic
energy and the Weizsacker term. The classical kinetic energy is seen to be
explicitly dependent on the electron phase and this has implications for the
development of accurate orbital-free kinetic-energy functionals. Also, there is
a direct connection between the classical kinetic energy and the angular
momentum and, across a row of the periodic table, the classical kinetic energy
component of the noninteracting kinetic energy generally increases as Z
increases.Comment: 10 pages, 1 figure. To appear in Theor Chem Ac
Targeting Illegal Immigration: Local Ordinate Action
From 1990 to 2005, estimates of the unauthorized alien population in the United States have risen from 3.5 million to 11.5 million people, a 325 percent increase. It has been the federal government's responsibility to prevent unauthorized immigration. However, a small number of localities have taken action over the past few years to prevent unauthorized immigration within their jurisdictions by passing a series of ordinances and resolutions. Some of the localities passed ordinances and resolutions targeting the businesses and landlords who hire and rent to unauthorized aliens, while others passed legislation targeting day labor centers, loitering, and government services. Consistent with findings made in other studies, we found that only approximately 100 localities have or are considering legislation that would impact their unauthorized alien communities.This document is adapted, but distinct from, a report on the topic prepared for the
U.S. Congressional Research Service
Quantization from an exponential distribution of infinitesimal action
A statistical model of quantization based on an exponential distribution of
infinitesimal action is proposed. Trajectory which does not extremize the
action along an infinitesimal short segment of path is allowed to occur with a
very small probability following an exponential law. Planck constant is argued
to give the average deviation from the infinitesimal stationary action.Comment: 15 pages, accepted for publication in Physica
N-Aryl mercaptoacetamides as potential multi-target inhibitors of metallo-β-lactamases (MBLs) and the virulence factor LasB from Pseudomonas aeruginosa
Increasing antimicrobial resistance is evolving to be one of the major threats to public health. To reduce the selection pressure and thus to avoid a fast development of resistance, novel approaches aim to target bacterial virulence instead of growth. Another strategy is to restore the activity of antibiotics already in clinical use. This can be achieved by the inhibition of resistance factors such as metallo-β-lactamases (MBLs). Since MBLs can cleave almost all β-lactam antibiotics, including the “last resort” carbapenems, their inhibition is of utmost importance. Here, we report on the synthesis and in vitro evaluation of N-aryl mercaptoacetamides as inhibitors of both clinically relevant MBLs and the virulence factor LasB from Pseudomonas aeruginosa. All tested N-aryl mercaptoacetamides showed low micromolar to submicromolar activities on the tested enzymes IMP-7, NDM-1 and VIM-1. The two most promising compounds were further examined in NDM-1 expressing Klebsiella pneumoniae isolates, where they restored the full activity of imipenem. Together with their LasB-inhibitory activity in the micromolar range, this class of compounds can now serve as a starting point for a multi-target inhibitor approach against both bacterial resistance and virulence, which is unprecedented in antibacterial drug discovery
Practice development: integrating theory to enhance role identity for occupational therapists
Boosting Anti-Inflammatory Potency of Zafirlukast by Designed Polypharmacology
Multitarget design offers access to bioactive small molecules with potentially superior efficacy and safety. Particularly multifactorial chronic inflammatory diseases demand multiple pharmacological interventions for stable treatment. By minor structural changes, we have developed a close analogue of the cysteinyl-leukotriene receptor antagonist zafirlukast that simultaneously inhibits soluble epoxide hydrolase and activates peroxisome proliferator-activated receptor \u3b3. The triple modulator exhibits robust anti-inflammatory activity in vivo and highlights the therapeutic potential of designed multitarget agents
Optical Arbitrary Waveform Measurement (OAWM) on the Silicon Photonic Platform
We demonstrate optical arbitrary waveform measurement (OAWM) using a silicon pho-tonic spectral slicer. Exploiting maximal-ratio combining (MRC), we demonstrate the viability of the scheme by reconstructing 100-GBd 64QAM signals with high quality
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