3,251 research outputs found
Midsummer renewal of oxygen within the hypolimnion
Following a very rainy period in the summer of 1950, oxygen temporarily reappeared in the hypolimnion of Lake Mendota. It is postulated that the oxygen was introduced there by density currents of cold, silt laden, well oxygenated runoff water
Interrogating Boundaries against Animals and Machines: Human Speciesism in British Newspapers
Humans favor and venerate their ingroups, while disregarding outgroups to the degree of dehumanizing them. We explore the social construction of such boundaries and its associated speciesism toward two nonhuman outgroups: animals and machines. For this, we analyzed UK newspaper coverages of the binaries Human–Animal and Human–Machine between 1995 and 2010. We quantified if and how tolerance toward ambiguous concepts that challenge and expand definitions of humanness (e.g., nonhuman primates, cyborgs) varied across time as well as with journalist gender, political leaning, and expertise. In this analysis, the ca. 1100 individual journalists stood as proxies for the British public and therefore as a human-ingroup subset. We found more tolerance toward intermediaries in broadsheet newspapers, females, and subject experts, as opposed to tabloids, males, and subject novices. Moreover, ambiguity tolerance hit a low during the year 2000, likely due to Western sociopolitical turbulence—potentially including wider societal stress over the landmark millennium year itself—attesting that ingroups become more closed during stressful times. Compared with the plasticity of the Human–Animal dichotomy, the Human–Machine binary was more rigid, indicating that the relative novelty of IT developments triggers increased caution and anxiety. Our research suggests that cognitive mechanisms facilitating human-ingroup protection are deep-rooted, albeit malleable according to changing socioeconomic conditions
Effect of feedback on the control of a two-level dissipative quantum system
We show that it is possible to modify the stationary state by a feedback
control in a two-level dissipative quantum system. Based on the geometric
control theory, we also analyze the effect of the feedback on the time-optimal
control in the dissipative system governed by the Lindblad master equation.
These effects are reflected in the function and
that characterize the optimal trajectories, as well as the
switching function and which characterize the switching
point in time for the time-optimal trajectory.Comment: 5 pages, 5 figure
Short Time Variation of Temperature in Lake Mendota, Wisconsin
Author Institution: F. T. Stone Institute of Hydrobiology, Put-in-Bay, Ohio, and Department of Meteorology, University of Wisconsin, Madiso
Currents in Lake Mendota, Wisconsin
Author Institution: F. T. Stone Institute of Hydrobiology, Put-in-Bay, Ohio, and Department of Meteorology, University of Wisconsin, Madiso
Search complexity and resource scaling for the quantum optimal control of unitary transformations
The optimal control of unitary transformations is a fundamental problem in
quantum control theory and quantum information processing. The feasibility of
performing such optimizations is determined by the computational and control
resources required, particularly for systems with large Hilbert spaces. Prior
work on unitary transformation control indicates that (i) for controllable
systems, local extrema in the search landscape for optimal control of quantum
gates have null measure, facilitating the convergence of local search
algorithms; but (ii) the required time for convergence to optimal controls can
scale exponentially with Hilbert space dimension. Depending on the control
system Hamiltonian, the landscape structure and scaling may vary. This work
introduces methods for quantifying Hamiltonian-dependent and kinematic effects
on control optimization dynamics in order to classify quantum systems according
to the search effort and control resources required to implement arbitrary
unitary transformations
AGMIAL: implementing an annotation strategy for prokaryote genomes as a distributed system
We have implemented a genome annotation system for prokaryotes called AGMIAL. Our approach embodies a number of key principles. First, expert manual annotators are seen as a critical component of the overall system; user interfaces were cyclically refined to satisfy their needs. Second, the overall process should be orchestrated in terms of a global annotation strategy; this facilitates coordination between a team of annotators and automatic data analysis. Third, the annotation strategy should allow progressive and incremental annotation from a time when only a few draft contigs are available, to when a final finished assembly is produced. The overall architecture employed is modular and extensible, being based on the W3 standard Web services framework. Specialized modules interact with two independent core modules that are used to annotate, respectively, genomic and protein sequences. AGMIAL is currently being used by several INRA laboratories to analyze genomes of bacteria relevant to the food-processing industry, and is distributed under an open source license
Photon storage in Lambda-type optically dense atomic media. II. Free-space model
In a recent paper [Gorshkov et al., Phys. Rev. Lett. 98, 123601 (2007)], we
presented a universal physical picture for describing a wide range of
techniques for storage and retrieval of photon wave packets in Lambda-type
atomic media in free space, including the adiabatic reduction of the photon
group velocity, pulse-propagation control via off-resonant Raman techniques,
and photon-echo based techniques. This universal picture produced an optimal
control strategy for photon storage and retrieval applicable to all approaches
and yielded identical maximum efficiencies for all of them. In the present
paper, we present the full details of this analysis as well some of its
extensions, including the discussion of the effects of non-degeneracy of the
two lower levels of the Lambda system. The analysis in the present paper is
based on the intuition obtained from the study of photon storage in the cavity
model in the preceding paper [Gorshkov et al., Phys. Rev. A 76, 033804 (2007)].Comment: 26 pages, 8 figures. V2: significant changes in presentation, new
references, higher resolution of figure
Photon storage in Lambda-type optically dense atomic media. I. Cavity model
In a recent paper [Gorshkov et al., Phys. Rev. Lett. 98, 123601 (2007)], we
used a universal physical picture to optimize and demonstrate equivalence
between a wide range of techniques for storage and retrieval of photon wave
packets in Lambda-type atomic media in free space, including the adiabatic
reduction of the photon group velocity, pulse-propagation control via
off-resonant Raman techniques, and photon-echo-based techniques. In the present
paper, we perform the same analysis for the cavity model. In particular, we
show that the retrieval efficiency is equal to C/(1+C) independent of the
retrieval technique, where C is the cooperativity parameter. We also derive the
optimal strategy for storage and, in particular, demonstrate that at any
detuning one can store, with the optimal efficiency of C/(1+C), any smooth
input mode satisfying T C gamma >> 1 and a certain class of resonant input
modes satisfying T C gamma ~ 1, where T is the duration of the input mode and 2
gamma is the transition linewidth. In the two subsequent papers of the series,
we present the full analysis of the free-space model and discuss the effects of
inhomogeneous broadening on photon storage.Comment: 16 pages, 2 figures. V2: significant changes in presentation, new
references, higher resolution of figure
Enhancing teaching and learning through dialogue: a student and staff partnership model
This paper explores a model for developing student and staff partnerships to enhance the quality of teaching and learning and situates the model in literature on student engagement. The model enables staff and students to step outside their normal roles and the traditional student-teacher relationship into a less pre-defined mode of interaction and liminal space where conversations about teaching and learning can take place. At the most transformative, this model enables academic staff to get a sense of learner perspectives and to view students as partners and collaborators while students develop insights into the perspectives of staff. The authors argue that the model represents an innovative approach to engaging students in a meaningful way in enhancing teaching and learning and has the potential to reframe the student-teacher relationship into a more collaborative one that goes beyond listening to students
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