211 research outputs found
The biogeography of community assembly: latitude and predation drive variation in community trait distribution in a guild of epifaunal crustaceans
While considerable evidence exists of biogeographic patterns in the intensity of species interactions, the influence of these patterns on variation in community structure is less clear. Studying how the distributions of traits in communities vary along global gradients can inform how variation in interactions and other factors contribute to the process of community assembly. Using a model selection approach on measures of trait dispersion in crustaceans associated with eelgrass (Zostera marina) spanning 30° of latitude in two oceans, we found that dispersion strongly increased with increasing predation and decreasing latitude. Ocean and epiphyte load appeared as secondary predictors; Pacific communities were more overdispersed while Atlantic communities were more clustered, and increasing epiphytes were associated with increased clustering. By examining how species interactions and environmental filters influence community structure across biogeographic regions, we demonstrate how both latitudinal variation in species interactions and historical contingency shape these responses. Community trait distributions have implications for ecosystem stability and functioning, and integrating large-scale observations of environmental filters, species interactions and traits can help us predict how communities may respond to environmental change
Strong magnetic coupling of an ultracold gas to a superconducting waveguide cavity
Placing an ensemble of ultracold atoms in the near field of a
superconducting coplanar waveguide resonator (CPWR) with one can
achieve strong coupling between a single microwave photon in the CPWR and a
collective hyperfine qubit state in the ensemble with kHz larger than the cavity line width of
kHz. Integrated on an atomchip such a system constitutes a hybrid quantum
device, which also can be used to interconnect solid-state and atomic qubits,
to study and control atomic motion via the microwave field, observe microwave
super-radiance, build an integrated micro maser or even cool the resonator
field via the atoms
Symmetries in Fluctuations Far from Equilibrium
Fluctuations arise universally in Nature as a reflection of the discrete
microscopic world at the macroscopic level. Despite their apparent noisy
origin, fluctuations encode fundamental aspects of the physics of the system at
hand, crucial to understand irreversibility and nonequilibrium behavior. In
order to sustain a given fluctuation, a system traverses a precise optimal path
in phase space. Here we show that by demanding invariance of optimal paths
under symmetry transformations, new and general fluctuation relations valid
arbitrarily far from equilibrium are unveiled. This opens an unexplored route
toward a deeper understanding of nonequilibrium physics by bringing symmetry
principles to the realm of fluctuations. We illustrate this concept studying
symmetries of the current distribution out of equilibrium. In particular we
derive an isometric fluctuation relation which links in a strikingly simple
manner the probabilities of any pair of isometric current fluctuations. This
relation, which results from the time-reversibility of the dynamics, includes
as a particular instance the Gallavotti-Cohen fluctuation theorem in this
context but adds a completely new perspective on the high level of symmetry
imposed by time-reversibility on the statistics of nonequilibrium fluctuations.
The new symmetry implies remarkable hierarchies of equations for the current
cumulants and the nonlinear response coefficients, going far beyond Onsager's
reciprocity relations and Green-Kubo formulae. We confirm the validity of the
new symmetry relation in extensive numerical simulations, and suggest that the
idea of symmetry in fluctuations as invariance of optimal paths has
far-reaching consequences in diverse fields.Comment: 8 pages, 4 figure
Oyster recruitment and climate change: do higher summer temperatures mean earlier and greater settlement in Pacific oysters?
Pacific oysters (Crassostrea gigas) are an economically beneficial product of the Pacific Northwest, introduced in the 1920s. In the 1940s governments initiated studies on the status and health of oysters in Pendrell Sound, BC (1949-1981) and Hood Canal WA (1942-1995). Seasonal surveys collected information on Pacific oyster settlement and timing through regular placement of spat collectors, usually clean shells. Simultaneously, water temperature was recorded. Because of temperatures in native ranges, reproduction in Pacific oysters is expected to improve in warmer years. Further, reproduction tends to be spatially limited to these two regions of the Salish Sea, where water temperatures can exceed 20° C in the summer. At some sites within regions, maximum seasonal recruitment ranged from less than 55 to nearly 10,000 per shell across summers, with peak timing that ranged from early July to early September. Pacific oysters tended to have earlier and higher settlement in warmer summers. The long term contribution of recruitment to feral populations and commercial stocks will hinge on temperature trends as well as interannual variability
The Halo Effect: Does In-Hospital Art Intervention Result in Improved Overall Patient Satisfaction?
Introduction
The positive impact of art therapy on medical patients has been well established in the literature.
• Association between visual art creation and maintenance / reconstruction of a positive identify throughout cancer treatment
• Decreased need for narcotic medications and patient length of stay following participation in guided imagery sessions
Despite an abundance of research on art therapy, few studies have examined impact of in-hospital art intervention on overall patient satisfaction.
Objectives
• Examine impact of Art from the Heart (AFTH), an in-hospital art intervention program, on patient interpretation of overall care received during hospital stay—the ‘halo effect’.
• Assess temporal, institution-level patient satisfaction survey scores following establishment of AFH intervention programhttps://scholarworks.uvm.edu/comphp_gallery/1272/thumbnail.jp
Efimov Trimers near the Zero-crossing of a Feshbach Resonance
Near a Feshbach resonance, the two-body scattering length can assume any
value. When it approaches zero, the next-order term given by the effective
range is known to diverge. We consider the question of whether this divergence
(and the vanishing of the scattering length) is accompanied by an anomalous
solution of the three-boson Schr\"odinger equation similar to the one found at
infinite scattering length by Efimov. Within a simple zero-range model, we find
no such solutions, and conclude that higher-order terms do not support Efimov
physics.Comment: 8 pages, no figures, final versio
Two-resonator circuit QED: A superconducting quantum switch
We introduce a systematic formalism for two-resonator circuit QED, where two
on-chip microwave resonators are simultaneously coupled to one superconducting
qubit. Within this framework, we demonstrate that the qubit can function as a
quantum switch between the two resonators, which are assumed to be originally
independent. In this three-circuit network, the qubit mediates a geometric
second-order circuit interaction between the otherwise decoupled resonators. In
the dispersive regime, it also gives rise to a dynamic second-order
perturbative interaction. The geometric and dynamic coupling strengths can be
tuned to be equal, thus permitting to switch on and off the interaction between
the two resonators via a qubit population inversion or a shifting of the qubit
operation point. We also show that our quantum switch represents a flexible
architecture for the manipulation and generation of nonclassical microwave
field states as well as the creation of controlled multipartite entanglement in
circuit QED. In addition, we clarify the role played by the geometric
interaction, which constitutes a fundamental property characteristic of
superconducting quantum circuits without counterpart in quantum-optical
systems. We develop a detailed theory of the geometric second-order coupling by
means of circuit transformations for superconducting charge and flux qubits.
Furthermore, we show the robustness of the quantum switch operation with
respect to decoherence mechanisms. Finally, we propose a realistic design for a
two-resonator circuit QED setup based on a flux qubit and estimate all the
related parameters. In this manner, we show that this setup can be used to
implement a superconducting quantum switch with available technology.Comment: Published in Phys. Rev. B, major changes, 24 pages, 8 figures, REVTeX
The biogeography of community assembly: latitude and predation drive variation in community trait distribution in a guild of epifaunal crustaceans
While considerable evidence exists of biogeographic patterns in the intensity of species interactions, the influence of these patterns on variation in community structure is less clear. Studying how the distributions of traits in communities vary along global gradients can inform how variation in interactions and other factors contribute to the process of community assembly. Using a model selection approach on measures of trait dispersion in crustaceans associated with eelgrass (Zostera marina) spanning 30 degrees of latitude in two oceans, we found that dispersion strongly increased with increasing predation and decreasing latitude. Ocean and epiphyte load appeared as secondary predictors; Pacific communities were more overdispersed while Atlantic communities were more clustered, and increasing epiphytes were associated with increased clustering. By examining how species interactions and environmental filters influence community structure across biogeographic regions, we demonstrate how both latitudinal variation in species interactions and historical contingency shape these responses. Community trait distributions have implications for ecosystem stability and functioning, and integrating large-scale observations of environmental filters, species interactions and traits can help us predict how communities may respond to environmental change.info:eu-repo/semantics/publishedVersio
"Go make your face known": collaborative working through the lens of personal relationships
Background: Collaborative working between professionals is a key component of integrated care. The academic literature on it largely focuses either on integration between health and social care or on the dynamics of power and identity between doctors and nurses. With the proliferation and extension of nursing roles, there is a need to examine collaborative working amongst different types of nurses.
Method: This study explored experiences of collaborative working amongst generalist and specialist nurses, in community and acute settings. We carried out semi-structured interviews, incorporating the Pictor technique, with 45 nurses, plus 33 other key stakeholders. Transcripts were analysed using Template Analysis. This article focuses on one major thematic area that emerged from the analysis: the significance of interpersonal relationships amongst nurses, and between them and other professionals, patients and carers.
Results: Relationship issues were ubiquitous in participants’ accounts of collaborative working. Good personal relationships facilitated collaboration; face-to-face interaction was especially valued. Relationships were recognized as requiring effort, especially in new roles. Organisational changes could disrupt productive personal networks.
Conclusion: Relationship issues are integral to successful collaborative working. Policy and practice leaders must take this into account in future service developments. Further research into collaborative relationships in different settings is needed
An inactivated vaccine made from a U.S. field isolate of porcine epidemic disease virus is immunogenic in pigs as demonstrated by a dose-titration
- …