12,253 research outputs found
A Hidden Broad-Line Region in the Weak Seyfert 2 Galaxy NGC 788
We have detected a broad H alpha emission line in the polarized flux spectrum
of the Seyfert 2 galaxy NGC 788, indicating that it contains an obscured
Seyfert 1 nucleus. While such features have been observed in ~15 other Seyfert
2s, this example is unusual because it has a higher fraction of galaxy
starlight in its spectrum, a lower average measured polarization, and a
significantly lower radio luminosity than other hidden Seyfert 1s discovered to
date. This demonstrates that polarized broad-line regions can be detected in
relatively weak classical Seyfert 2s, and illustrates why well-defined,
reasonably complete spectropolarimetric surveys at H alpha are necessary in
order to assess whether or not all Seyfert 2s are obscured Seyfert 1s.Comment: 10 pages using (AASTEX) aaspp4.sty and 4 postscript figures.
Publications of the Astronomical Society of the Pacific, Research Notes, in
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Using a smartphone app to identify signs of pre-eclampsia and/or worsening blood pressure
Background
Hypertensive disorders of pregnancy complicate 10% of pregnancies and can have serious consequences.
Aims
To explore the experiences of pregnant women with a history of hypertension using an innovative home blood pressure monitoring device.
Methods
A qualitative study using a grounded theory approach was undertaken. Data were collected through semi-structured interviews. Women were given a blood pressure machine to monitor their blood pressure daily. They inserted their blood pressure results on a smartphone app and answered questions for signs of pre-eclampsia. Participants were followed up every 2 weeks.
Findings
The results suggested that women wanted a holistic care pathway for the management of hypertension in pregnancy. Three subcategories (‘empowerment’, ‘comparison of care pathways’ and ‘continuity of care’) were also identified.
Conclusions
The traditional management of hypertension in pregnancy is not holistic. The home blood pressure service was accepted by women and incorporated elements of holistic care but more is required to meet the standard of care that women need
Resonance absolute quantum reflection at selected energies
The possibility of the resonance reflection (100 % at maximum) is revealed.
The corresponding exactly solvable models with the controllable numbers of
resonances, their positions and widths are presented.Comment: 5 pages, 2 figure
Methods of Euthanasia
The killing of animals is perhaps the most consistent task faced by veterinarians in all facets of the profession. In private or institutionalized practice, in almost any area of active research, in meat inspection, and in pathology and diagnostic services, one common shared activity is the actual or supervisory killing of animals. The motivations, methods, and considerations are myriad, but the process of inflicting death on a variety of living creatures is an inseparable, undeniable part of the veterinary profession
Compassion fatigue among nurses working with older adults
Nurses who care for older patients are exposed to significant suffering and loss that can lead to the development of compassion fatigue and burnout. An exploratory descriptive study was conducted to assess compassion fatigue, burnout, and compassion satisfaction in a group of 42 nurses who worked on a geriatric medicine unit using the Professional Quality of Life (ProQOL) compassion satisfaction and compassion fatigue 5 scale. Nurses reported average levels of compassion fatigue, burnout, and compassion satisfaction. However, new nurses reported higher levels of compassion fatigue (p < .01) and burnout (p = .02) than experienced nurses. Findings suggest the need to purposely build a supportive environment that focuses on new nurses to reduce compassion fatigue and burnout while enhancing compassion satisfaction
Functional renormalization group at large N for random manifolds
We introduce a method, based on an exact calculation of the effective action
at large N, to bridge the gap between mean field theory and renormalization in
complex systems. We apply it to a d-dimensional manifold in a random potential
for large embedding space dimension N. This yields a functional renormalization
group equation valid for any d, which contains both the O(epsilon=4-d) results
of Balents-Fisher and some of the non-trivial results of the Mezard-Parisi
solution thus shedding light on both. Corrections are computed at order O(1/N).
Applications to the problems of KPZ, random field and mode coupling in glasses
are mentioned
Degree of quantum correlation required to speed up a computation
The one clean qubit model of quantum computation (DQC1) efficiently
implements a computational task that is not known to have a classical
alternative. During the computation, there is never more than a small but
finite amount of entanglement present, and it is typically vanishingly small in
the system size. In this paper, we demonstrate that there is nothing unexpected
hidden within the DQC1 model -- Grover's Search, when acting on a mixed state,
provably exhibits a speed-up over classical with guarantees as to the presence
of only vanishingly small amounts of quantum correlations (entanglement and
quantum discord) -- while arguing that this is not an artefact of the
oracle-based construction. We also present some important refinements in the
evaluation of how much entanglement may be present in DQC1, and how the typical
entanglement of the system must be evaluated.Comment: 7 pages, 3 figure
A modified Oster-Murray-Harris mechanical model of morphogenesis
There are two main modeling paradigms for biological pattern formation in developmental biology: chemical prepattern models and cell aggregation models. This paper focuses on an example of a cell aggregation model, the mechanical model developed by Oster, Murray, and Harris [Development, 78 (1983), pp. 83--125]. We revisit the Oster--Murray--Harris model and find that, due to the infinitesimal displacement assumption made in the original version of this model, there is a restriction on the types of boundary conditions that can be prescribed. We derive a modified form of the model which relaxes the infinitesimal displacement assumption. We analyze the dynamics of this model using linear and multiscale nonlinear analysis and show that it has the same linear behavior as the original Oster--Murray--Harris model. Nonlinear analysis, however, predicts that the modified model will allow for a wider range of parameters where the solution evolves to a bounded steady state. The results from both analyses are verified through numerical simulations of the full nonlinear model in one and two dimensions. The increased range of boundary conditions that are well-posed, as well as a wider range of parameters that yield bounded steady states, renders the modified model more applicable to, and more robust for, comparisons with experiments
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