3,402 research outputs found
Continuous interfaces with disorder: Even strong pinning is too weak in 2 dimensions
We consider statistical mechanics models of continuous height effective
interfaces in the presence of a delta-pinning at height zero. There is a
detailed mathematical understanding of the depinning transition in 2 dimensions
without disorder. Then the variance of the interface height w.r.t. the Gibbs
measure stays bounded uniformly in the volume for any positive pinning force
and diverges like the logarithm of the pinning force when it tends to zero.
How does the presence of a quenched disorder term in the Hamiltonian modify
this transition? We show that an arbitarily weak random field term is enough to
beat an arbitrarily strong delta-pinning in 2 dimensions and will cause
delocalization. The proof is based on a rigorous lower bound for the overlap
between local magnetizations and random fields in finite volume. In 2
dimensions it implies growth faster than the volume which is a contradiction to
localization. We also derive a simple complementary inequality which shows that
in higher dimensions the fraction of pinned sites converges to one when the
pinning force tends to infinity.Comment: 8 page
A simple fluctuation lower bound for a disordered massless random continuous spin model in d=2
We prove a finite volume lower bound of the order of the squareroot of log N
on the delocalization of a disordered continuous spin model (resp. effective
interface model) in d = 2 in a box of size N . The interaction is assumed to be
massless, possibly anharmonic and dominated from above by a Gaussian. Disorder
is entering via a linear source term. For this model delocalization with the
same rate is proved to take place already without disorder. We provide a bound
which is uniform in the configuration of the disorder, and so our proof shows
that randomness will only enhance fluctuations
Kalikow-type decomposition for multicolor infinite range particle systems
We consider a particle system on with real state space and
interactions of infinite range. Assuming that the rate of change is continuous
we obtain a Kalikow-type decomposition of the infinite range change rates as a
mixture of finite range change rates. Furthermore, if a high noise condition
holds, as an application of this decomposition, we design a feasible perfect
simulation algorithm to sample from the stationary process. Finally, the
perfect simulation scheme allows us to forge an algorithm to obtain an explicit
construction of a coupling attaining Ornstein's -distance for two
ordered Ising probability measures.Comment: Published in at http://dx.doi.org/10.1214/12-AAP882 the Annals of
Applied Probability (http://www.imstat.org/aap/) by the Institute of
Mathematical Statistics (http://www.imstat.org
Experimental experience in design education as a resource for innovative thinking: The case of Bruno Munari
AbstractDesign education in general includes various design fields such as product design, graphic design, communication design and design in engineering. Designing as an activity captures all these various fields. Design refers basically to a problem solving method, a creative problem solving approach and relevant processes. Design as an activity has always been considered as a creative tool. Design education mainly focuses on enhancing creative approaches with various 2D and 3D project based basic design studies. As the tools of designing developed in parallel with technology, the core structure of the education is based on a model with creative and analytical aspects: Designerly way of thinking aims at originality and uniqueness. Today the need for innovation has become more evident than ever. The main purpose of the paper is to explore and to identify the relationship between creativity, innovation and design related to design education. Bruno Munari(Milano, 1907-1998) as a designer and a design educator, is one of the prominent names reflecting innovation and creativity in the history of Italian Design. His innovative contribution to Italian Design is reinforced by his experimental design educator background in research for creativity. The paper aims at exploring the educational structures through history of design and design education that leads to creative thinking and nurture sustainable innovation through the case study of Bruno Munari's works as a designer and as an educator
Typical Gibbs configurations for the 1d Random Field Ising Model with long range interaction
We study a one--dimensional Ising spin systems with ferromagnetic,
long--range interaction decaying as n^{-2+\a}, \a \in [0,\frac 12], in the
presence of external random fields. We assume that the random fields are given
by a collection of symmetric, independent, identically distributed real random
variables, gaussian or subgaussian with variance . We show that for
temperature and variance of the randomness small enough, with an overwhelming
probability with respect to the random fields, the typical configurations,
within volumes centered at the origin whose size grow faster than any power of
, % {\bf around the origin} are intervals of spins followed by
intervals of spins whose typical length is \simeq
\th^{-\frac{2}{(1-2\a)}} for 0\le \a<1/2 and
for \a=1/2
Comparison of different dispersion models with tracer experiment
An intercomparison between three different models is presented. The simulated case is a tracer experiment performed in complex terrain. Two dispersion models are initialised with a meteorological model that can use as input the ECMWF analysis only or both these analysis and local measurements. The results demonstrate that the best performances are obtained by using the dispersion models
coupled with a meteorological model. Moreover the Lagrangian model seems to slightly better perform when the local measurements are accounted for
Timing is everything: dance aesthetics depend on the complexity of movement kinematics
What constitutes a beautiful action? Research into dance aesthetics has largely focussed on subjective features like familiarity with the observed movement, but has rarely studied objective features like speed or acceleration. We manipulated the kinematic complexity of observed actions by creating dance sequences that varied in movement timing, but not in movement trajectory. Dance-naïve participants rated the dance videos on speed, effort, reproducibility, and enjoyment. Using linear mixed-effects modeling, we show that faster, more predictable movement sequences with varied velocity profiles are judged to be more effortful, less reproducible, and more aesthetically pleasing than slower sequences with more uniform velocity profiles. Accordingly, dance aesthetics depend not only on which movements are being performed but on how movements are executed and linked into sequences. The aesthetics of movement timing may apply across culturally-specific dance styles and predict both preference for and perceived difficulty of dance, consistent with information theory and effort heuristic accounts of aesthetic appreciation
Searching for antimicrobial photosensitizers among a panel of BODIPYs
In recent years, antimicrobial Photodynamic Therapy (aPDT) gained increasing attention for its potential to inhibit the growth and spread of microorganisms, both as free-living cells and/or embedded in biofilm communities. In this scenario, compounds belonging to the family of boron-dipyrromethenes (BODIPYs) represent a very promising class of photosensitizers for applications in antimicrobial field. In this study, twelve non-ionic and three cationic BODIPYs were assayed for the inactivation of Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans. As expected, S. aureus showed to be very sensitive to BODIPYs and mild conditions were sufficient to reach good rates of photoinactivation with both neutral and monocationic ones. Surprisingly, one neutral compound (named B9 in this study) resulted the best BODIPY to photoinactivate P. aeruginosa PAO1. The photoinactivation of C. albicans was reached with both neutral and mono-cationic BODIPYs. Furthermore, biofilms of the three model microorganisms were challenged with BODIPYs in light-based antimicrobial technique. S. aureus biofilms were successfully inhibited with milder conditions than those applied to P. aeruginosa and C. albicans. Notably, it was possible to eradicate 24-h-old biofilms of both S. aureus and P. aeruginosa. In conclusion, this study supports the potential of neutral BODIPYs as pan-antimicrobial PSs. Graphical abstract: [Figure not available: see fulltext.]
Nodular lymphocyte predominant Hodgkin lymphoma behaves as a distinct clinical entity with good outcome: evidence from 14-year followup in the West of Scotland Cancer Network
Clinically and biologically, nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) has much more in common with germinal-center derived B-cell non-Hodgkin lymphoma (NHL) than with classical Hodgkin lymphoma (cHL). Management of NLPHL remains controversial. In a 14-year multicenter series, 69 cases were analyzed, and the median follow-up was 53 months (range 11–165.) B-symptoms were present in only 4.3% of patients, and 81.1% of patients had stage I/II disease. Treatment was with radiotherapy (53.6%), chemotherapy (21.7%), combined modality (17.4%), and observation (7.2%). In all, 10.1% of patients relapsed and 2.9% of patients developed high-grade transformation to DLBCL. All relapses and transformations were salvageable. No patient died of their disease. The 5-year relapse-free survival was 92%, transformation-free survival 98.4%, and overall survival 100%. We conclude that NLPHL behaves as a distinct clinical entity, often presenting at an early stage without risk factors. It has an excellent outcome. It may be possible, in early-stage disease, to reduce the intensity of therapy in NLPHL, to single-modality radiotherapy, without affecting OS
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