2,393 research outputs found
Micromagnetic Domain Structures in Cylindrical Nickel Dots
The magnetic domain structures of cylindrical nickel dots (diameters from 40 nm to 1700 nm) with anisotropy parallel to the cylinder axis is predicted by the ratio of the dot diameter to the stripe period of unpatterned films with the same perpendicular anisotropy. The dominant domain structure for a given ratio increases in complexity as the ratio increases. We present evidence for the full micromagnetic domain structure for the simplest cases
Interferometric scattering enables fluorescence-free electrokinetic trapping of single nanoparticles in free solution
Anti-Brownian traps confine single particles in free solution by closed-loop
feedback forces that directly counteract Brownian motion. The extended-duration
measurement of trapped objects allows detailed characterization of
photophysical and transport properties, as well as observation of infrequent or
rare dynamics. However, this approach has been generally limited to particles
that can be tracked by fluorescent emission. Here we present the
Interferometric Scattering Anti-Brownian ELectrokinetic trap (ISABEL trap),
which uses interferometric scattering rather than fluorescence to monitor
particle position. By decoupling the ability to track (and therefore trap) a
particle from collection of its spectroscopic data, the ISABEL trap enables
confinement and extended study of single particles that do not fluoresce, that
only weakly fluoresce, or which exhibit intermittent fluorescence or
photobleaching. This new technique significantly expands the range of nanoscale
objects that may be investigated at the single-particle level in free solution.Comment: Manuscript and SI; videos available upon reques
Biology and Ecology of the Atlantic Stingray, Dasyatis sabina (Pisces: Dasyatidae) in North Carolina and Georgia
The seasonality, distribution, ecology, movements, catch per unit effort, breeding season, and length-weight relationships for the Atlantic stingray, Dasyatis sabina, trawled in North Carolina (1973 through 1976) and Georgia (1967 through 1969) are compared and discussed. Occurrences in relation to water temperature, salinity, and oxygen content are also reported and compared with previous literature. Dispelling popular belief, D. sabina throughout its range is a minor numerical component of the fish faunas studied
Weighted maximal regularity estimates and solvability of non-smooth elliptic systems II
We continue the development, by reduction to a first order system for the
conormal gradient, of \textit{a priori} estimates and solvability for
boundary value problems of Dirichlet, regularity, Neumann type for divergence
form second order, complex, elliptic systems. We work here on the unit ball and
more generally its bi-Lipschitz images, assuming a Carleson condition as
introduced by Dahlberg which measures the discrepancy of the coefficients to
their boundary trace near the boundary. We sharpen our estimates by proving a
general result concerning \textit{a priori} almost everywhere non-tangential
convergence at the boundary. Also, compactness of the boundary yields more
solvability results using Fredholm theory. Comparison between classes of
solutions and uniqueness issues are discussed. As a consequence, we are able to
solve a long standing regularity problem for real equations, which may not be
true on the upper half-space, justifying \textit{a posteriori} a separate work
on bounded domains.Comment: 76 pages, new abstract and few typos corrected. The second author has
changed nam
Resolvent Estimates in L^p for the Stokes Operator in Lipschitz Domains
We establish the resolvent estimates for the Stokes operator in
Lipschitz domains in , for . The result, in particular, implies that the Stokes operator in a
three-dimensional Lipschitz domain generates a bounded analytic semigroup in
for (3/2)-\varep < p< 3+\epsilon. This gives an affirmative answer to a
conjecture of M. Taylor.Comment: 28 page. Minor revision was made regarding the definition of the
Stokes operator in Lipschitz domain
Refined asymptotics for the infinite heat equation with homogeneous Dirichlet boundary conditions
The nonnegative viscosity solutions to the infinite heat equation with
homogeneous Dirichlet boundary conditions are shown to converge as time
increases to infinity to a uniquely determined limit after a suitable time
rescaling. The proof relies on the half-relaxed limits technique as well as
interior positivity estimates and boundary estimates. The expansion of the
support is also studied
"Caring for Insiderness": Phenomenologically informed insights that can guide practice.
Understanding the ââinsiderââ perspective has been a pivotal strength of qualitative research. Further than this, within the more applied fields in which the human activity of ââcaringââ takes place, such understanding of ââwhat it is likeââ for people from within their lifeworlds has also been acknowledged as the foundational starting point in order for ââcareââ to be caring. But we believe that more attention needs to be paid to this foundational generic phenomenon: what it means to understand the ââinsidernessââ of another, but more importantly, how to act on this in caring ways. We call this human phenomenon ââcaring for insiderness.ââ Drawing on existing phenomenological studies of marginal caring situations at the limits of caring capability, and through a process of phenomenologically oriented reflection, we interrogated some existential themes implicit in these publications that could lead to deeper insights for both theoretical and applied purposes. The paper provides direction for practices of caring by highlighting some dangers as well as some remedies along this path
Performance, Politics and Media: How the 2010 British General Election leadership debates generated âtalkâ amongst the electorate.
During the British General Election 2010 a major innovation was introduced in part to improve engagement: a series of three live televised leadership debates took place where the leader of each of the three main parties, Labour, Liberal Democrat and Conservative, answered questions posed by members of the public and subsequently debated issues pertinent to the questions. In this study we consider these potentially ground breaking debates as the kind of event that was likely to generate discussion. We investigate various aspects of the âtalkâ that emerged as a result of watching the debates. As an exploratory study concerned with situated accounts of the participants experiences we take an interpretive perspective. In this paper we outline the meta-narratives (of talk) associated with the viewing of the leadership debates that were identified, concluding our analysis by suggesting that putting a live debate on television and promoting and positioning it as a major innovation is likely to mean that is how the audience will make sense of it â as a media event
Observing Interprofessional Simulation
© 2019, Springer Nature Switzerland AG. This chapter has a particular focus on the observersâ role in simulation-based learning activities. Simulation-based learning is often organised so that participants rotates between active participation in the scenario and participation as observers. The research examples provided show that the conditions for learning are related to the locations where and the ways the observers are situated, and to how the instructions to the observers are formulated. Arguments are put forward that the observersâ role in simulation has unexploited potential for developing skills of noticing
Null sets of harmonic measure on NTA domains: Lipschitz approximation revisited
We show the David-Jerison construction of big pieces of Lipschitz graphs
inside a corkscrew domain does not require its surface measure be upper Ahlfors
regular. Thus we can study absolute continuity of harmonic measure and surface
measure on NTA domains of locally finite perimeter using Lipschitz
approximations. A partial analogue of the F. and M. Riesz Theorem for simply
connected planar domains is obtained for NTA domains in space. As a consequence
every Wolff snowflake has infinite surface measure.Comment: 22 pages, 6 figure
- âŠ