2,444 research outputs found
Concepts of Community in Environmental Disputes: Farmersville and Western New York\u27s Garbage Wars
Non-universal Casimir Effect in Saturated Superfluid He Films at T
Measurements of Casimir effects in He films in the vicinity of the bulk
superfluid transition temperature have been carried out, where
changes in the film thickness and the superfluid density are both monitored as
a function of temperature. The Kosterlitz-Thouless superfluid onset temperature
in the film is found to occur just as the Casimir dip in the film thickness
from critical fluctuations becomes evident. Additionally, a new film-thickening
effect is observed precisely at when the temperature is swept
extremely slowly. We propose that this is a non-universal Casimir effect
arising from the viscous suppression of second sound modes in the film.Comment: 5 pages, 6 figures, corrected an equation, small change to fit valu
From Lyapunov modes to the exponents for hard disk systems
We demonstrate the preservation of the Lyapunov modes by the underlying
tangent space dynamics of hard disks.
This result is exact for the zero modes and correct to order for
the transverse and LP modes where is linear in the mode number.
For sufficiently large mode numbers the dynamics no longer preserves the mode
structure.
We propose a Gram-Schmidt procedure based on orthogonality with respect to
the centre space that determines the values of the Lyapunov exponents for the
modes.
This assumes a detailed knowledge of the modes, but from that predicts the
values of the exponents from the modes.
Thus the modes and the exponents contain the same information
A novel vaccine platform using glucan particles for induction of protective responses against Francisella tularensis and other pathogens
Vaccines are considered the bedrock of preventive medicine. However, for many pathogens, it has been challenging to develop vaccines that stimulate protective, long-lasting immunity. We have developed a novel approach using beta-1,3-D-glucans (BGs), natural polysaccharides abundantly present in fungal cell walls, as a biomaterial platform for vaccine delivery. BGs simultaneously provide for receptor-targeted antigen delivery to specialized antigen-presenting cells together with adjuvant properties to stimulate antigen-specific and trained non-specific immune responses. This review focuses on various approaches of using BG particles (GPs) to develop bacterial and fungal vaccine candidates. A special case history for the development of an effective GP tularaemia vaccine candidate is highlighted
Dynamic Low-Stretch Trees via Dynamic Low-Diameter Decompositions
Spanning trees of low average stretch on the non-tree edges, as introduced by
Alon et al. [SICOMP 1995], are a natural graph-theoretic object. In recent
years, they have found significant applications in solvers for symmetric
diagonally dominant (SDD) linear systems. In this work, we provide the first
dynamic algorithm for maintaining such trees under edge insertions and
deletions to the input graph. Our algorithm has update time
and the average stretch of the maintained tree is , which matches
the stretch in the seminal result of Alon et al.
Similar to Alon et al., our dynamic low-stretch tree algorithm employs a
dynamic hierarchy of low-diameter decompositions (LDDs). As a major building
block we use a dynamic LDD that we obtain by adapting the random-shift
clustering of Miller et al. [SPAA 2013] to the dynamic setting. The major
technical challenge in our approach is to control the propagation of updates
within our hierarchy of LDDs: each update to one level of the hierarchy could
potentially induce several insertions and deletions to the next level of the
hierarchy. We achieve this goal by a sophisticated amortization approach.
We believe that the dynamic random-shift clustering might be useful for
independent applications. One of these applications is the dynamic spanner
problem. By combining the random-shift clustering with the recent spanner
construction of Elkin and Neiman [SODA 2017]. We obtain a fully dynamic
algorithm for maintaining a spanner of stretch and size with amortized update time for any integer . Compared to the state-of-the art in this regime
[Baswana et al. TALG '12], we improve upon the size of the spanner and the
update time by a factor of .Comment: To be presented at the 51st Annual ACM Symposium on the Theory of
Computing (STOC 2019); abstract shortened to respect the arXiv limit of 1920
character
Bringing Racial Justice to the Courtroom and Community: Race Matters for Juvenile Justice and the Charlotte Model
This article describes regional institutional organizing efforts to bring racial justice to the Charlotte courts and community through a collaborative called Race Matters for Juvenile Justice (RMJJ). The authors explain community and institutional organizing in-depth using the example of minority overrepresentation in the juvenile justice system, but recognize the pervasiveness of racial and ethnic disparities. Moreover, as the Race Matters for Juvenile Justice-Charlotte Model has gained national prominence, many jurisdictions seek to replicate the collaborative and the authors, therefore, provide RMJJ’s history as well as strategies for changing the narrative through communication and education, workforce development, data and research, community collaboration, practice change, and legislation reform
Third sound measurements of superfluid He films on multiwall carbon nanotubes below 1K
Third sound is studied for superfluid films of 4He adsorbed on multiwall
carbon nanotubes packed into an annular resonator. The third sound is generated
with mechanical oscillation of the cell, and detected with carbon bolometers. A
filling curve at temperatures near 250 mK shows oscillations in the third sound
velocity, with maxima at the completion of the 4th and 5th atomic layers. Sharp
changes in the Q factor of the third sound are found at partial layer fillings.
Temperature sweeps at a number of fill points show strong broadening effects on
the Kosterlitz-Thouless (KT) transition, and rapidly increasing dissipation, in
qualitative agreement with the predictions of Machta and Guyer. At the 4th
layer completion there is a sudden reduction of the transition temperature
, and then a recovery back to linear variation with temperature,
although the slope is considerably smaller than the KT prediction. Some of
these effects may be related to changes in the gas-liquid coexistence regions.Comment: 5 pages, 5 figures, Proceedings of LT2
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