294 research outputs found
From controlled trials to clinical practice: monitoring transmyocardial revascularization use and outcomes
Entangled Light in Moving Frames
We calculate the entanglement between a pair of polarization-entangled photon
beams as a function of the reference frame, in a fully relativistic framework.
We find the transformation law for helicity basis states and show that, while
it is frequency independent, a Lorentz transformation on a momentum-helicity
eigenstate produces a momentum-dependent phase. This phase leads to changes in
the reduced polarization density matrix, such that entanglement is either
decreased or increased, depending on the boost direction, the rapidity, and the
spread of the beam.Comment: 4 pages and 3 figures. Minor corrections, footnote on optimal basis
state
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The Ultra-Potent and Selective TLR8 Agonist VTX-294 Activates Human Newborn and Adult Leukocytes
Background: Newborns display distinct immune responses that contribute to susceptibility to infection and reduced vaccine responses. Toll-like receptor (TLR) agonists may serve as vaccine adjuvants, when given individually or in combination, but responses of neonatal leukocytes to many TLR agonists are diminished. TLR8 agonists are more effective than other TLR agonists in activating human neonatal leukocytes in vitro, but little is known about whether different TLR8 agonists may distinctly activate neonatal leukocytes. We characterized the in vitro immuno-stimulatory activities of a novel benzazepine TLR8 agonist, VTX-294, in comparison to imidazoquinolines that activate TLR8 (R-848; (TLR7/8) CL075; (TLR8/7)), with respect to activation of human newborn and adult leukocytes. Effects of VTX-294 and R-848 in combination with monophosphoryl lipid A (MPLA; TLR4) were also assessed. Methods: TLR agonist specificity was assessed using TLR-transfected HEK293 cells expressing a NF-κB reporter gene. TLR agonist-induced cytokine production was measured in human newborn cord and adult peripheral blood using ELISA and multiplex assays. Newborn and adult monocytes were differentiated into monocyte-derived dendritic cells (MoDCs) and TLR agonist-induced activation assessed by cytokine production (ELISA) and co-stimulatory molecule expression (flow cytometry). Results: VTX-294 was ∼100x more active on TLR8- than TLR7-transfected HEK cells (EC50, ∼50 nM vs. ∼5700 nM). VTX-294-induced TNF and IL-1β production were comparable in newborn cord and adult peripheral blood, while VTX-294 was ∼ 1 log more potent in inducing TNF and IL-1β production than MPLA, R848 or CL075. Combination of VTX-294 and MPLA induced greater blood TNF and IL-1β responses than combination of R-848 and MPLA. VTX-294 also potently induced expression of cytokines and co-stimulatory molecules HLA-DR and CD86 in human newborn MoDCs. Conclusions: VTX-294 is a novel ultra-potent TLR8 agonist that activates newborn and adult leukocytes and is a candidate vaccine adjuvant in both early life and adulthood
How to observe a coherent superposition of an atom and a molecule
We demonstrate that it is possible, in principle, to perform a Ramsey-type
interference experiment to exhibit a coherent superposition of a single atom
and a diatomic molecule. This gedanken experiment, based on the techniques of
Aharonov and Susskind [Phys. Rev. 155, 1428 (1967)], explicitly violates the
commonly-accepted superselection rule that forbids coherent superpositions of
eigenstates of differing atom number. This interference experiment makes use of
a Bose-Einstein condensate as a reference frame with which to perform the
coherent operations analogous to Ramsey pulses. We also investigate an
analogous gedanken experiment to exhibit a coherent superposition of a single
boson and a fermion, violating the commonly-accepted superselection rule
forbidding coherent superpositions of states of differing particle statistics;
in this case, the reference frame is realized by a multi-mode state of many
fermions. This latter case reproduces all of the relevant features of Ramsey
interferometry, including Ramsey fringes over many repetitions of the
experiment. However, the apparent inability of this proposed experiment to
produce well-defined relative phases between two distinct systems each
described by a coherent superposition of a boson and a fermion demonstrates
that there are additional, outstanding requirements to fully ``lift'' the
univalence superselection rule.Comment: 17 pages, 1 figure, comments welcome, published version (minor
changes
Quantum dynamics in ultra-cold atomic physics
We review recent developments in the theory of quantum dynamics in ultra-cold
atomic physics, including exact techniques, but focusing on methods based on
phase-space mappings that are appli- cable when the complexity becomes
exponentially large. These phase-space representations include the truncated
Wigner, positive-P and general Gaussian operator representations which can
treat both bosons and fermions. These phase-space methods include both
traditional approaches using a phase-space of classical dimension, and more
recent methods that use a non-classical phase-space of increased
dimensionality. Examples used include quantum EPR entanglement of a four-mode
BEC, time-reversal tests of dephasing in single-mode traps, BEC quantum
collisions with up to 106 modes and 105 interacting particles, quantum
interferometry in a multi-mode trap with nonlinear absorp- tion, and the theory
of quantum entropy in phase-space. We also treat the approach of variational
optimization of the sampling error, giving an elementary example of a nonlinear
oscillator
Prioritising Informed Health Choices Key Concepts for those impacted by cancer: a protocol [version 1; peer review: 2 approved]
Background: Few areas of health have been as insidiously influenced by misinformation as cancer. Thus, interventions that can help people impacted by cancer reduce the extent to which they are victims of misinformation are necessary. The Informed Health Choices (IHC) initiative has developed Key Concepts that can be used in the development of interventions for evaluating the trustworthiness of claims about the effects of health treatments. We are developing an online education programme called Informed Health Choices-Cancer (IHC-C) based on the IHC Key Concepts. We will provide those impacted by cancer with the knowledge and skills necessary to think critically about the reliability of health information and claims and make informed choices. Methods: We will establish a steering group (SG) of 12 key stakeholders, including oncology specialists and academics. In addition, we will establish a patient and public involvement (PPI) panel of 20 people impacted by cancer. After training the members on the Key Concepts and the prioritisation process, we will conduct a two-round prioritisation process. In the first round, 12 SG members and four PPI panel members will prioritise Key Concepts for inclusion. In the second round, the remaining 16 PPI members will undertake the prioritisation based on the prioritised Key Concepts from the first round. Participants in both rounds will use a structured judgement form to rate the importance of the Key Concepts for inclusion in the online IHC-C programme. A consensus meeting will be held, where members will reach a consensus on the Key Concepts to be included and rank the order in which the prioritised Key Concepts will be addressed in the IHC-C programme. Conclusions: At the end of this process, we will identify which Key Concepts should be included and the order in which they should be addressed in the IHC-C programme
Reader technique as a source of variability in determining malaria parasite density by microscopy
BACKGROUND: Accurate identification and quantification of malaria parasites are critical for measuring clinical trial outcomes. Positive and negative diagnosis is usually sufficient for the assessment of therapeutic outcome, but vaccine or prophylactic drug trials require measuring density of infection as a primary endpoint. Microscopy is the most established and widely-used technique for quantifying parasite densities in the blood. METHODS: Results obtained by 24–27 expert malaria microscopists, who had independently read 895 slides from 35 donors, were analysed to understand how reader technique contributes to discrepancy in measurements of parasite density over a wide range of densities. RESULTS: Among these 35 donations, standard deviations ranged from 30% to 250% of the mean parasite density and the percent discrepancy was inversely correlated with the mean parasite density. The number of white blood cells indexed and whether parasites were counted in the thick film or thin film were shown to significantly contribute to discrepancy amongst microscopists. CONCLUSION: Errors in microscopy measurements are not widely appreciated or addressed but have serious consequences for efficacy trials, including possibly abandoning promising vaccine candidates
Marketing Actions and the Value of Customer Assets: A Framework for Customer Asset Management
This article develops a framework for assessing how marketing actions affect customers’lifetime value to the firm. The framework is organized around four critical actions that firms must take to effectively manage the asset value of the customer base: database creation, market segmentation, forecasting customer purchase behavior, and resource allocation. In this framework, customer lifetime value is treated as a dynamic construct, that is, it influences the eventual allocation of marketing resources but is also influenced by that allocation. By viewing customers as assets and systematically managing these assets, a firm can identify the most appropriate marketing actions to acquire, maintain, and enhance customer assets and thereby maximize financial returns. The article discusses in detail how to assess customer lifetime value and manage customers as assets. Then, it identifies key research challenges in studying customer asset management and the managerial challenges associated with implementing effective customer asset management practices.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline
Maxwell Duality, Lorentz Invariance, and Topological Phase
We discuss the Maxwell electromagnetic duality relations between the
Aharonov-Bohm, Aharonov-Casher, and He-McKellar-Wilkens topological phases,
which allows a unified description of all three phenomena. We also elucidate
Lorentz transformations that allow these effects to be understood in an
intuitive fashion in the rest frame of the moving quantum particle. Finally, we
propose two experimental schemes for measuring the He-McKellar-Wilkens phase.Comment: 10 pages, 2 figure
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