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International Change and technological evolution in the Fashion Industry
textabstractThe aim of this research is to sketch out the parameters of the fashion industry. Whilst, without
doubt fashion is a means of personal and cultural expression, it is also an industry. The industrial and
economic aspects have been relatively under-researched. We highlight the fact that the fashion industry
is fast evolving, and growing. Traditional economic analyses have under-examined some of the
crucial drivers of change in this sector but these are all important issues for a number of reasons. First,
the local and global consequences of the transformation of the fashion industry help us to understand
the challenges facing urban and regional economies, particularly in Europe. Second, the fashion industry,
like the cultural industries more generally, is leading a new form of economic development that
blends qualitative elements and quantitative forms, a culturalisation of economic action. In so doing
we also raise three questions, one has already been alluded to: what is the âfashion industryâ; and following
this, a second: is the fashion industry the same, or different, to other cultural industries? Finally,
in relation to the dynamics of change, we point to the role of situatedness: the importance of place and
institutional embedding
Vibrations and fractional vibrations of rods, plates and Fresnel pseudo-processes
Different initial and boundary value problems for the equation of vibrations
of rods (also called Fresnel equation) are solved by exploiting the connection
with Brownian motion and the heat equation. The analysis of the fractional
version (of order ) of the Fresnel equation is also performed and, in
detail, some specific cases, like , 1/3, 2/3, are analyzed. By means
of the fundamental solution of the Fresnel equation, a pseudo-process ,
with real sign-varying density is constructed and some of its properties
examined. The equation of vibrations of plates is considered and the case of
circular vibrating disks is investigated by applying the methods of
planar orthogonally reflecting Brownian motion within . The composition of
F with reflecting Brownian motion yields the law of biquadratic heat
equation while the composition of with the first passage time of
produces a genuine probability law strictly connected with the Cauchy process.Comment: 33 pages,8 figure
Centre-of-mass like superposition of Ornstein-Uhlenbeck processes: A pathway to non-autonomous stochastic differential equations and to fractional diffusion
We consider an ensemble of OrnsteinâUhlenbeck processes featuring a population of relaxation times and a population of noise amplitudes that characterize the heterogeneity of the ensemble. We show that the centre-of-mass like variable corresponding to this ensemble is statistically equivalent to a process driven by a non-autonomous stochastic differential equation with time-dependent drift and a white noise. In particular, the time scaling and the density function of such variable are driven by the population of timescales and of noise amplitudes, respectively. Moreover, we show that this variable is equivalent in distribution to a randomly-scaled Gaussian process, i.e., a process built by the product of a Gaussian process times a non-negative independent random variable. This last result establishes a connection with the so-called generalized grey Brownian motion and suggests application to model fractional anomalous diffusion in biological systems.âMarco Polo Programmeâ (University of Bologna
Analytical tools for solitons and periodic waves corresponding to phonons on Lennard-Jones lattices in helical proteins
9 pages, 13 figures.-- PACS nrs.: 05.45.Yv, 87.15.-v.-- PMID: 15783440 [PubMed].We study the propagation of solitons along the hydrogen bonds of an alpha helix. Modeling the hydrogen and peptide bonds with Lennard-Jones potentials, we show that the solitons can appear spontaneously and have long lifetimes. Remarkably, even if no explicit solution is known for the Lennard-Jones potential, the solitons can be characterized analytically with a good quantitative agreement using formulas for a Toda potential with parameters fitted to the Lennard-Jones potential. We also discuss and show the robustness of the family of periodic solutions called cnoidal waves, corresponding to phonons. The soliton phenomena described in the simulations of alpha helices may help to explain recent x-ray experiments on long alpha helices in Rhodopsin where a long lifetime of the vibrational modes has been observed.Peer reviewe
Noise-induced macroscopic bifurcations in globally-coupled chaotic units
Large populations of globally-coupled identical maps subjected to independent
additive noise are shown to undergo qualitative changes as the features of the
stochastic process are varied. We show that for strong coupling, the collective
dynamics can be described in terms of a few effective macroscopic degrees of
freedom, whose deterministic equations of motion are systematically derived
through an order parameter expansion.Comment: Phys. Rev. Lett., accepte
Lagrangian transport through an ocean front in the North-Western Mediterranean Sea
We analyze with the tools of lobe dynamics the velocity field from a
numerical simulation of the surface circulation in the Northwestern
Mediterranean Sea. We identify relevant hyperbolic trajectories and their
manifolds, and show that the transport mechanism known as the `turnstile',
previously identified in abstract dynamical systems and simplified model flows,
is also at work in this complex and rather realistic ocean flow. In addition
nonlinear dynamics techniques are shown to be powerful enough to identify the
key geometric structures in this part of the Mediterranean. In particular the
North Balearic Front, the westernmost part of the transition zone between
saltier and fresher waters in the Western Mediterranean is interpreted in terms
of the presence of a semipermanent ``Lagrangian barrier'' across which little
transport occurs. Our construction also reveals the routes along which this
transport happens. Topological changes in that picture, associated with the
crossing by eddies and that may be interpreted as the breakdown of the front,
are also observed during the simulation.Comment: 34 pages, 6 (multiple) figures. Version with higher quality figures
available from
http://www.imedea.uib.es/physdept/publications/showpaper_en.php?indice=1764 .
Problems with paper size fixe
Convolution-type derivatives, hitting-times of subordinators and time-changed -semigroups
In this paper we will take under consideration subordinators and their
inverse processes (hitting-times). We will present in general the governing
equations of such processes by means of convolution-type integro-differential
operators similar to the fractional derivatives. Furthermore we will discuss
the concept of time-changed -semigroup in case the time-change is
performed by means of the hitting-time of a subordinator. We will show that
such time-change give rise to bounded linear operators not preserving the
semigroup property and we will present their governing equations by using again
integro-differential operators. Such operators are non-local and therefore we
will investigate the presence of long-range dependence.Comment: Final version, Potential analysis, 201
Near-surface transport pathways in the north Atlantic Ocean : looking for throughput from the subtropical to the subpolar gyre
Author Posting. © American Meteorological Society, 2011. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 41 (2011): 911â925, doi:10.1175/2011JPO4498.1.Motivated by discrepancies between Eulerian transport estimates and the behavior of Lagrangian surface drifters, near-surface transport pathways and processes in the North Atlantic are studied using a combination of data, altimetric surface heights, statistical analysis of trajectories, and dynamical systems techniques. Particular attention is paid to the issue of the subtropical-to-subpolar intergyre fluid exchange. The velocity field used in this study is composed of a steady drifter-derived background flow, upon which a time-dependent altimeter-based perturbation is superimposed. This analysis suggests that most of the fluid entering the subpolar gyre from the subtropical gyre within two years comes from a narrow region lying inshore of the Gulf Stream core, whereas fluid on the offshore side of the Gulf Stream is largely prevented from doing so by the Gulf Stream core, which acts as a strong transport barrier, in agreement with past studies. The transport barrier near the Gulf Stream core is robust and persistent from 1992 until 2008. The qualitative behavior is found to be largely independent of the Ekman drift.This work was supported by the
National Science Foundation Grants CMG-82469600 and
CMG-82579600 and by the Office of Naval Research
Grant ONR-13108700
Platelet activation in the postoperative period after lung transplantation
Objective
During lung transplantation, cells in the pulmonary parenchyma are subjected to ischemia, hypothermic storage, and reperfusion injury. Platelets, whose granular contents include adhesion receptors, chemokines, and coactivating substances that activate inflammatory and coagulant cascades, likely play a critical role in the lung allograft response to ischemia and reperfusion. The platelet response to the pulmonary allograft, however, has never been studied. Here we report significant platelet activation immediately after lung transplantation.
Methods
We performed a prospective cohort study comparing markers of platelet activation in patients undergoing lung transplantation and patients undergoing nontransplant thoracotomy. Plasma levels of soluble P-selectin, soluble CD40 ligand, and plateletâleukocyte conjugates were measured before surgery, after skin closure, and at 6 postoperative hours.
Results
Both soluble P-selectin and soluble CD40 ligand levels increased significantly after lung transplantation but not after thoracotomy. Additionally, plateletâmonocyte conjugate fluorescence was significantly higher after lung transplantation than after thoracotomy alone.
Conclusion
These findings suggest that platelet activation is significantly increased after lung transplantation beyond that expected from the postoperative state. The increase in circulating plateletâmonocyte conjugates suggests an important interaction between platelets and inflammatory cells. Further research should examine whether platelet activation affects early graft function after lung transplantation
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