Long time, large scale limit of the Wigner transform for a system of linear oscillators in one dimension

We consider the long time, large scale behavior of the Wigner transform W_\eps(t,x,k) of the wave function corresponding to a discrete wave equation on a 1-d integer lattice, with a weak multiplicative noise. This model has been introduced in Basile, Bernardin, and Olla to describe a system of interacting linear oscillators with a weak noise that conserves locally the kinetic energy and the momentum. The kinetic limit for the Wigner transform has been shown in Basile, Olla, and Spohn. In the present paper we prove that in the unpinned case there exists $\gamma_0>0$ such that for any $\gamma\in(0,\gamma_0]$ the weak limit of W_\eps(t/\eps^{3/2\gamma},x/\eps^{\gamma},k), as \eps\ll1, satisfies a one dimensional fractional heat equation $\partial_t W(t,x)=-\hat c(-\partial_x^2)^{3/4}W(t,x)$ with $\hat c>0$. In the pinned case an analogous result can be claimed for W_\eps(t/\eps^{2\gamma},x/\eps^{\gamma},k) but the limit satisfies then the usual heat equation

The hypoxia-inducible factor-responsive proteins semaphorin 4D and vascular endothelial growth factor promote tumor growth and angiogenesis in oral squamous cell carcinoma

Growth and metastasis of solid tumors requires induction of angiogenesis to ensure the delivery of oxygen, nutrients and growth factors to rapidly dividing transformed cells. Through either mutations, hypoxia generated by cytoreductive therapies, or when a malignancy outgrows its blood supply, tumor cells undergo a change from an avascular to a neovascular phenotype, a transition mediated by the hypoxia-inducible factor (HIF) family of transcriptional regulators. Vascular endothelial growth factor (VEGF) is one example of a gene whose transcription is stimulated by HIF. VEGF plays a crucial role in promoting tumor growth and survival by stimulating new blood vessel growth in response to such stresses as chemotherapy or radiotherapy-induced hypoxia, and it therefore has become a tempting target for neutralizing antibodies in the treatment of advanced neoplasms. Emerging evidence has shown that the semaphorins, proteins originally associated with control of axonal growth and immunity, are regulated by changes in oxygen tension as well and may play a role in tumor-induced angiogenesis. Through the use of RNA interference, in vitro and in vivo angiogenesis assays and tumor xenograft experiments, we demonstrate that expression of semaphorin 4D (SEMA4D), which is under the control of the HIF-family of transcription factors, cooperates with VEGF to promote tumor growth and vascularity in oral squamous cell carcinoma (OSCC). We use blocking antibodies to show that targeting SEMA4D function along with VEGF could represent a novel anti-angiogenic therapeutic strategy for the treatment of OSCC and other solid tumors

Semaphorin 4D cooperates with VEGF to promote angiogenesis and tumor progression

The semaphorins and plexins comprise a family of cysteine-rich proteins implicated in control of nerve growth and development and regulation of the immune response. Our group and others have found that Semaphorin 4D (SEMA4D) and its receptor, Plexin-B1, play an important role in tumor-induced angiogenesis, with some neoplasms producing SEMA4D in a manner analogous to vascular endothelial growth factor (VEGF) in order to attract Plexin-B1-expressing endothelial cells into the tumor for the purpose of promoting growth and vascularity. While anti-VEGF strategies have been the focus of most angiogenesis inhibition research, such treatment can lead to upregulation of pro-angiogenic factors that can compensate for the loss of VEGF, eventually leading to failure of therapy. Here, we demonstrate that SEMA4D cooperates with VEGF to promote angiogenesis in malignancies and can perform the same function in a setting of VEGF blockade. We also show the potential value of inhibiting SEMA4D/Plexin-B1 signaling as a complementary mechanism to anti-VEGF treatment, particularly in VEGF inhibitor-resistant tumors, suggesting that this may represent a novel treatment for some cancer

The Western Australian Clinical Senate as a Model for State-Wide Clinical Engagement

International reforms in healthcare have established the principal that embracing clinical engagement can drive healthcare reform and improved safety and quality outcomes. Most attention has focussed on how clinicians might be engaged at a local or hospital level. However, healthcare reforms are usually initiated at a state or national level. Less attention has gone into exploring the key elements of a model to achieve clinical engagement at state or national level. This paper explores the key elements of a successful state-wide clinical engagement model including culture and leadership, membership, decision-making processes and accountability and discusses how the current model of the Western Australian Clinical Senate addresses these elements. This model may be applicable in other jurisdictions and healthcare systems

Thermal conductivity in harmonic lattices with random collisions

We review recent rigorous mathematical results about the macroscopic behaviour of harmonic chains with the dynamics perturbed by a random exchange of velocities between nearest neighbor particles. The random exchange models the effects of nonlinearities of anharmonic chains and the resulting dynamics have similar macroscopic behaviour. In particular there is a superdiffusion of energy for unpinned acoustic chains. The corresponding evolution of the temperature profile is governed by a fractional heat equation. In non-acoustic chains we have normal diffusivity, even if momentum is conserved.Comment: Review paper, to appear in the Springer Lecture Notes in Physics volume "Thermal transport in low dimensions: from statistical physics to nanoscale heat transfer" (S. Lepri ed.

Diffractive Higgs Production from Intrinsic Heavy Flavors in the Proton

We propose a novel mechanism for exclusive diffractive Higgs production $pp \to p H p$ in which the Higgs boson carries a significant fraction of the projectile proton momentum. This mechanism will provide a clear experimental signal for Higgs production due to the small background in this kinematic region. The key assumption underlying our analysis is the presence of intrinsic heavy flavor components of the proton bound state, whose existence at high light-cone momentum fraction $x$ has growing experimental and theoretical support. We also discuss the implications of this picture for exclusive diffractive quarkonium and other channels.Comment: 30 pages, 5 figure

Studies of multiplicity in relativistic heavy-ion collisions

In this talk I'll review the present status of charged particle multiplicity measurements from heavy-ion collisions. The characteristic features of multiplicity distributions obtained in Au+Au collisions will be discussed in terms of collision centrality and energy and compared to those of p+p collisions. Multiplicity measurements of d+Au collisions at 200 GeV nucleon-nucleon center-of-mass energy will also be discussed. The results will be compared to various theoretical models and simple scaling properties of the data will be identified.Comment: "Focus on Multiplicity" Internationsl Workshop on Particle Multiplicity in Relativistic Heavy Ion Collisions, Bari, Italy, June 17-19, 2003, 16 pages, 15 figure

Variations of Wave Energy Power in Shoaling Zone of Benin Coastal Zone

Today, we observe at the population level, that the improvement in comfort is accompanied by an increase in the electrical energy required. The predicted exhaustion of fossil energy resources maintains some speculation. Their unequal geographical distribution justifies the energy dependence of Benin overlooked from outside. So it is urgent to explore the various sources of renewable energy available to Benin. In this work, using measurements made ​​by the Millennium Challenge Account (MCA-Benin) as part of the extension of the port of Cotonou, with Boussinesq equations (Peregrine) and Stokes waves dispersion relation, we characterized the variations of various swell parameters (height, wavelength, velocities) in the shoaling zone on the study site and proceeded to estimate variations in wave energy power from deep waters to the bathymetric breaking point. Finally, the zone with high energy power (where the conversion of this energy into electrical energy would be profitable) of these waves is highlighted on the site, the local water depth at the point of breaking waves is evaluated and results obtained allowed to justify the very energetic character take by these swells on this coast when they are close to the beach

The QCD sign problem and dynamical simulations of random matrices

At nonzero quark chemical potential dynamical lattice simulations of QCD are hindered by the sign problem caused by the complex fermion determinant. The severity of the sign problem can be assessed by the average phase of the fermion determinant. In an earlier paper we derived a formula for the microscopic limit of the average phase for general topology using chiral random matrix theory. In the current paper we present an alternative derivation of the same quantity, leading to a simpler expression which is also calculable for finite-sized matrices, away from the microscopic limit. We explicitly prove the equivalence of the old and new results in the microscopic limit. The results for finite-sized matrices illustrate the convergence towards the microscopic limit. We compare the analytical results with dynamical random matrix simulations, where various reweighting methods are used to circumvent the sign problem. We discuss the pros and cons of these reweighting methods.Comment: 34 pages, 3 figures, references added, as published in JHE

Identifying Cultural and Cognitive Proximity between Managers and Customers in Tornio and Haparanda Cross Border Region

Daily intercultural interactions in cross-border regions such as those between customers and managers can be a source of knowledge and ideas. However, such interactions can pose distinctive constraints and opportunities for learning and exchange of ideas. This study adopts a relatively fine–grained quantitative approach to study elements of cognitive and cultural proximity which have a major impact on these interactions. It is based on a survey of 91 managers of small service firms and 312 customers in the twin city of Tornio and Haparanda on the border between Finland and Sweden. Seven elements of proximity were identified and measured. Six elements of perceived cognitive and cultural proximity including values, conservative values towards new ideas, knowledge and use of technology, use of a foreign language, sufficiently focusing or providing specific details and ways of solving problems were found significant in terms of shaping perceptions of Swedish and Finnish managers and customers, which shape these interactions. The results enhance our understanding of how daily cross-border intercultural can be examined in the context of cross-border regional knowledge transfer