4,454 research outputs found
Remote Vendor Cigarette Sales, Tribal Sovereignty, and the Jenkins Act: Can I Get a Remedy?
The article examines the statutory and jurisprudential issues pertaining to remote vendor sales of cigarettes from tribal lands. This author suggests that the Jenkins Act contains mechanisms that are intended to ensure the collection of state cigarette excise taxes while leaving intact the doctrines of tribal sovereignty and sovereign immunity. The author concludes that the Jenkins Act can accomplish these goals if properly enforced
Measurement crosstalk between two phase qubits coupled by a coplanar waveguide
We analyze the measurement crosstalk between two flux-biased phase qubits
coupled by a resonant coplanar waveguide cavity. After the first qubit is
measured, the superconducting phase can undergo damped oscillations resulting
in an a.c. voltage that produces a frequency chirped noise signal whose
frequency crosses that of the cavity. We show experimentally that the coplanar
waveguide cavity acts as a bandpass filter that can significantly reduce the
crosstalk signal seen by the second qubit when its frequency is far from the
cavity's resonant frequency. We present a simple classical description of the
qubit behavior that agrees well with the experimental data. These results
suggest that measurement crosstalk between superconducting phase qubits can be
reduced by use of linear or possibly nonlinear resonant cavities as coupling
elements.Comment: 4 pages, 3 figure
Circuit QED scheme for realization of the Lipkin-Meshkov-Glick model
We propose a scheme in which the Lipkin-Meshkov-Glick model is realized
within a circuit QED system. An array of N superconducting qubits interacts
with a driven cavity mode. In the dispersive regime, the cavity mode is
adiabatically eliminated generating an effective model for the qubits alone.
The characteristic long-range order of the Lipkin-Meshkov-Glick model is here
mediated by the cavity field. For a closed qubit system, the inherent second
order phase transition of the qubits is reflected in the intensity of the
output cavity field. In the broken symmetry phase, the many-body ground state
is highly entangled. Relaxation of the qubits is analyzed within a mean-field
treatment. The second order phase transition is lost, while new bistable
regimes occur.Comment: 5 pages, 2 figure
Tripartite interactions between two phase qubits and a resonant cavity
The creation and manipulation of multipartite entangled states is important
for advancements in quantum computation and communication, and for testing our
fundamental understanding of quantum mechanics and precision measurements.
Multipartite entanglement has been achieved by use of various forms of quantum
bits (qubits), such as trapped ions, photons, and atoms passing through
microwave cavities. Quantum systems based on superconducting circuits have been
used to control pair-wise interactions of qubits, either directly, through a
quantum bus, or via controllable coupling. Here, we describe the first
demonstration of coherent interactions of three directly coupled
superconducting quantum systems, two phase qubits and a resonant cavity. We
introduce a simple Bloch-sphere-like representation to help one visualize the
unitary evolution of this tripartite system as it shares a single microwave
photon. With careful control and timing of the initial conditions, this leads
to a protocol for creating a rich variety of entangled states. Experimentally,
we provide evidence for the deterministic evolution from a simple product
state, through a tripartite W-state, into a bipartite Bell-state. These
experiments are another step towards deterministically generating multipartite
entanglement in superconducting systems with more than two qubits
Sideband Cooling Micromechanical Motion to the Quantum Ground State
The advent of laser cooling techniques revolutionized the study of many
atomic-scale systems. This has fueled progress towards quantum computers by
preparing trapped ions in their motional ground state, and generating new
states of matter by achieving Bose-Einstein condensation of atomic vapors.
Analogous cooling techniques provide a general and flexible method for
preparing macroscopic objects in their motional ground state, bringing the
powerful technology of micromechanics into the quantum regime. Cavity opto- or
electro-mechanical systems achieve sideband cooling through the strong
interaction between light and motion. However, entering the quantum regime,
less than a single quantum of motion, has been elusive because sideband cooling
has not sufficiently overwhelmed the coupling of mechanical systems to their
hot environments. Here, we demonstrate sideband cooling of the motion of a
micromechanical oscillator to the quantum ground state. Entering the quantum
regime requires a large electromechanical interaction, which is achieved by
embedding a micromechanical membrane into a superconducting microwave resonant
circuit. In order to verify the cooling of the membrane motion into the quantum
regime, we perform a near quantum-limited measurement of the microwave field,
resolving this motion a factor of 5.1 from the Heisenberg limit. Furthermore,
our device exhibits strong-coupling allowing coherent exchange of microwave
photons and mechanical phonons. Simultaneously achieving strong coupling,
ground state preparation and efficient measurement sets the stage for rapid
advances in the control and detection of non-classical states of motion,
possibly even testing quantum theory itself in the unexplored region of larger
size and mass.Comment: 13 pages, 7 figure
Implicit Reasons for Disclosure of the Use of Complementary Health Approaches (CHA): a Consumer Commitment Perspective
Background: Disclosure of the use of complementary health approaches (CHA) is an important yet understudied health behaviour with important implications for patient care. Yet research into disclosure of CHA has been atheoretical and neglected the role of health beliefs. Purpose: Using a consumer commitment model of CHA use as a guiding conceptual framework, the current study tests the hypotheses that perceived positive CHA outcomes (utilitarian values) and positive CHA beliefs (symbolic values) are associated with disclosure of CHA to conventional-care providers in a nationally representative US sample. Methods: From a sample of 33,594 with CHA use information from the 2012 National Health Interview Survey (NHIS), a subsample of 7,348 who used CHA within the past 12 months was analysed. The 2012 NHIS is a cross-sectional survey of the non-institutionalized US adult population, which includes the most recent nationally representative CHA use data. Results: The 63.2 % who disclosed CHA use were older, less educated, and had visited a health-care provider in the past year. Weighted logistic regression analyses controlling for demographic variables revealed that those who disclosed were more likely to report experiencing positive psychological (improved coping and well-being) and physical outcomes (better sleep, improved health) from CHA, and hold positive CHA-related beliefs. Conclusions: CHA users who perceive physical and psychological benefits from CHA use, and who hold positive attitudes towards CHA are more likely to disclose their CHA use. Findings support the relevance of a consumer commitment perspective for understanding CHA disclosure, and suggest CHA disclosure as an important proactive health behaviour that warrants further attention
Reasons for continuing use of Complementary and Alternative Medicine (CAM) in students: a consumer commitment model
Background:
Research on continued CAM use has been largely atheoretical and has not considered the broader range of psychological and behavioral factors that may be involved. The purpose of this study was to test a new conceptual model of commitment to CAM use that implicates utilitarian (trust in CAM) and symbolic (perceived fit with CAM) in psychological and behavioral dimensions of CAM commitment.
Methods:
A student sample of CAM consumers, (N= 159) completed a survey about their CAM use, CAM-related values, intentions for future CAM use, CAM word-of-mouth behavior, and perceptions of being an ongoing CAM consumer.
Results:
Analysis revealed that the utilitarian, symbolic, and CAM commitment variables were significantly related, with râs ranging from .54 to .73. A series hierarchical regression analyses controlling for relevant demographic variables found that the utilitarian and symbolic values uniquely accounted for significant and substantial proportion of the variance in each of the three CAM commitment indicators (R2
from .37 to .57).
Conclusions:
The findings provide preliminary support for the new model that posits that CAM commitment is a multi-dimensional psychological state with behavioral indicators. Further research with large-scale samples and longitudinal designs is warranted to understand the potential value of the new model
Developing and Testing an AI Empathy Agent
Generation and Rating of the EA Response Bank âą Response bank generated by service users via online survey presenting 5 different SU scenarios; âą Responses then screened for duplicates and usability by research team and rated by service users via online survey; âą Responses then rated by SUs via online survey to generate ratings to be used in development of the AI underpinning the EA
Radiation hardness qualification of PbWO4 scintillation crystals for the CMS Electromagnetic Calorimeter
This is the Pre-print version of the Article. The official published version can be accessed from the link below - Copyright @ 2010 IOPEnsuring the radiation hardness of PbWO4 crystals was one of the main priorities during the construction of the electromagnetic calorimeter of the CMS experiment at CERN. The production on an industrial scale of radiation hard crystals and their certification over a period of several years represented a difficult challenge both for CMS and for the crystal suppliers. The present article reviews the related scientific and technological problems encountered
Search for Doubly-Charged Higgs Boson Production at HERA
A search for the single production of doubly-charged Higgs bosons H^{\pm \pm}
in ep collisions is presented. The signal is searched for via the Higgs decays
into a high mass pair of same charge leptons, one of them being an electron.
The analysis uses up to 118 pb^{-1} of ep data collected by the H1 experiment
at HERA. No evidence for doubly-charged Higgs production is observed and mass
dependent upper limits are derived on the Yukawa couplings h_{el} of the Higgs
boson to an electron-lepton pair. Assuming that the doubly-charged Higgs only
decays into an electron and a muon via a coupling of electromagnetic strength
h_{e \mu} = \sqrt{4 \pi \alpha_{em}} = 0.3, a lower limit of 141 GeV on the
H^{\pm\pm} mass is obtained at the 95% confidence level. For a doubly-charged
Higgs decaying only into an electron and a tau and a coupling h_{e\tau} = 0.3,
masses below 112 GeV are ruled out.Comment: 15 pages, 3 figures, 1 tabl
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