1,368 research outputs found
A Case Study: The Role of Compassionate Cities, Healthy Cities, and UN Sustainable Development Goals in City Leadership and Planning
This research is a case study examining the relevance of three holistic city frameworksâCompassionate Cities, Healthy Cities, and UN Sustainable Development Goalsâto the intentional or tacit thinking of city leaders, community leaders, and activists of Marina, California. Beginning with a discussion of the origin and development of the three frameworks, the study occurred in three phases: Phase I involved interviewing the five elected leaders, city manager, community development leaders, and two planners; Phase II consisted of a survey of appointed city leaders and community organizers and activists; and Phase III was an analysis of relevant public discourse, drawing from local newspapers, social media, and city council and other public agenciesâ agendas and public records. In the background is a discussion on the challenges of a city that is transitioning from a former U.S. military base support city to one that embraces a new generation of urban dwellers, becoming an economically and socially sustainable municipality. This dissertation is available in open access at AURA: Antioch University Repository and Archive, http://aura.antioch.edu/ and OhioLINK ETD Center, https://etd.ohiolink.edu
Scaling of entanglement at quantum phase transition for two-dimensional array of quantum dots
With Hubbard model, the entanglement scaling behavior in a two-dimensional
itinerant system is investigated. It has been found that, on the two sides of
the critical point denoting an inherent quantum phase transition (QPT), the
entanglement follows different scalings with the size just as an order
parameter does. This fact reveals the subtle role played by the entanglement in
QPT as a fungible physical resource
Modeling the X-ray - UV Correlations in NGC 7469
We model the correlated X-ray - UV observations of NGC 7469, for which well
sampled data in both these bands have been obtained recently in a
multiwavelength monitoring campaign. To this end we derive the transfer
function in wavelength \ls and time lag \t, for reprocessing hard (X-ray)
photons from a point source to softer ones (UV-optical) by an infinite plane
(representing a cool, thin accretion disk) located at a given distance below
the X-ray source, under the assumption that the X-ray flux is absorbed and
emitted locally by the disk as a black body of temperature appropriate to the
incident flux. Using the observed X-ray light curve as input we have computed
the expected continuum UV emission as a function of time at several wavelengths
(\l \l 1315 \AA, \l \l 6962 \AA, \l \l 15000 \AA, \l \l 30000 \AA) assuming
that the X-ray source is located one \sc radius above the disk plane, with the
mass of the black hole and the latitude angle of the observer
relative to the disk plane as free parameters. We have searched the parameter
space of black hole masses and observer azimuthal angles but we were unable to
reproduce UV light curves which would resemble, even remotely, those observed.
We also explored whether particular combinations of the values of these
parameters could lead to light curves whose statistical properties (i.e. the
autocorrelation and cross correlation functions) would match those
corresponding to the observed UV light curve at \l \l 1315 \AA. Even though we
considered black hole masses as large as M no such match was
possible. Our results indicate that some of the fundamental assumptions of this
model will have to be modified to obtain even approximate agreement between the
observed and model X-ray - UV light curves.Comment: 16 pages, 13 figures, ApJ in pres
Defining childhood severe falciparum malaria for intervention studies.
Background Clinical trials of interventions designed to prevent severe falciparum malaria in children require a clear endpoint. The internationally accepted definition of severe malaria is sensitive, and appropriate for clinical purposes. However, this definition includes individuals with severe nonmalarial disease and coincident parasitaemia, so may lack specificity in vaccine trials. Although there is no âgold standardâ individual test for severe malaria, malaria-attributable fractions (MAFs) can be estimated among groups of children using a logistic model, which we use to test the suitability of various case definitions as trial endpoints. Methods and Findings A total of 4,583 blood samples were taken from well children in cross-sectional surveys and from 1,361 children admitted to a Kenyan District hospital with severe disease. Among children under 2 y old with severe disease and over 2,500 parasites per microliter of blood, the MAFs were above 85% in moderate- and low-transmission areas, but only 61% in a high-transmission area. HIV and malnutrition were not associated with reduced MAFs, but gastroenteritis with severe dehydration (defined by reduced skin turgor), lower respiratory tract infection (clinician's final diagnosis), meningitis (on cerebrospinal fluid [CSF] examination), and bacteraemia were associated with reduced MAFs. The overall MAF was 85% (95% confidence interval [CI] 83.8%â86.1%) without excluding these conditions, 89% (95% CI 88.4%â90.2%) after exclusions, and 95% (95% CI 94.0%â95.5%) when a threshold of 2,500 parasites/ÎŒl was also applied. Applying a threshold and exclusion criteria reduced sensitivity to 80% (95% CI 77%â83%). Conclusions The specificity of a case definition for severe malaria is improved by applying a parasite density threshold and by excluding children with meningitis, lower respiratory tract infection (clinician's diagnosis), bacteraemia, and gastroenteritis with severe dehydration, but not by excluding children with HIV or malnutrition
Mediated tunable coupling of flux qubits
It is sketched how a monostable rf- or dc-SQUID can mediate an inductive
coupling between two adjacent flux qubits. The nontrivial dependence of the
SQUID's susceptibility on external flux makes it possible to continuously tune
the induced coupling from antiferromagnetic (AF) to ferromagnetic (FM). In
particular, for suitable parameters, the induced FM coupling can be
sufficiently large to overcome any possible direct AF inductive coupling
between the qubits.
The main features follow from a classical analysis of the multi-qubit
potential. A fully quantum treatment yields similar results, but with a
modified expression for the SQUID susceptibility.
Since the latter is exact, it can also be used to evaluate the
susceptibility--or, equivalently, energy-level curvature--of an isolated
rf-SQUID for larger shielding and at degenerate flux bias, i.e., a (bistable)
qubit. The result is compared to the standard two-level (pseudospin) treatment
of the anticrossing, and the ensuing conclusions are verified numerically.Comment: REVTeX 4, 16 pp., 4 EPS figures. N.B.: "Alec" is my first, and
"Maassen van den Brink" my family name. v2: major expansion and rewriting,
new title and co-author; to appear in New Journal of Physics special issue
(R. Fazio, ed.
- âŠ