On Sharp Interface Limits for Diffuse Interface Models for Two-Phase Flows

We discuss the sharp interface limit of a diffuse interface model for a two-phase flow of two partly miscible viscous Newtonian fluids of different densities, when a certain parameter \epsilon>0 related to the interface thickness tends to zero. In the case that the mobility stays positive or tends to zero slower than linearly in \epsilon we will prove that weak solutions tend to varifold solutions of a corresponding sharp interface model. But, if the mobility tends to zero faster than \epsilon^3 we will show that certain radially symmetric solutions tend to functions, which will not satisfy the Young-Laplace law at the interface in the limit.Comment: 27 pages, 1 figur

Local Well-Posedness for Relaxational Fluid Vesicle Dynamics

We prove the local well-posedness of a basic model for relaxational fluid vesicle dynamics by a contraction mapping argument. Our approach is based on the maximal $L_p$-regularity of the model's linearization.Comment: 29 page

Using questionnaires through an existing administrative system: a new approach to health interview surveys

This paper reviews recent developments in the field of health interview procedures, and their contribution to decentralized health planning. Their importance is reflected in the growing awareness that the perception of health problems by the beneficiaries is an important element in the success or failure of a primary health care (PHC) strategy for disease control and health improvement. The ‘indirect' health interview procedure represents a methodological evolution of the traditional interview approach, by the fact that questionnaires are not administered directly by the investigators or their field staff to the chosen key informants. They are distributed through an existing administrative system and self-administered by the recipients. This reduces the costs of such surveys, and allows large areas to be screened rapidly. The paper describes ongoing research designed to test this approach in seven African countries. Methodological problems and limitations, the most important of which is that it is not appropriate for individual diagnosis, are also discussed. This approach is best used as a screening strategy to identify high risk communities, on which health resources can then be concentrate

Partial regularity for minimizers of quasiconvex functionals with general growth

We prove a partial regularity result for local minimizers of quasiconvex variational integrals with general growth. The main tool is an improved A-harmonic approximation, which should be interesting also for classical growth.Comment: 23 page

On sharp interface limits for diffuse interface models for two-phase flows

We discuss the sharp interface limit of a diffuse interface model for a two-phase flow of two partly miscible viscous Newtonian fluids of different densities, when a certain parameter ϵ>0 related to the interface thickness tends to zero. In the case that the mobility stays positive or tends to zero slower than linearly in ϵ we will prove that weak solutions tend to varifold solutions of a corresponding sharp interface model. But, if the mobility tends to zero faster than ϵ3 we will show that certain radially symmetric solutions tend to functions, which will not satisfy the Young-Laplace law at the interface in the limit

Efficacious, effective, and embedded interventions: Implementation research in infectious disease control

Background: Research in infectious disease control is heavily skewed towards high end technology; development of new drugs, vaccines and clinical interventions. Oft ignored, is the evidence to inform the best strategies that ensure the embedding of interventions into health systems and amongst populations. In this paper we undertake an analysis of the challenge in the development of research for the sustainable implementation of disease control interventions. Results: We highlight the fundamental differences between the research paradigms associated with the development of technologies and interventions for disease control on the one hand and the research paradigms required for enhancing the sustainable uptake of those very same interventions within the communities on the other. We provide a definition for implementation research in an attempt to underscore its critical role and explore the multidisciplinary science needed to address the challenges in disease control. Conclusion: The greatest value for money in health research lies in the sustainable and effective implementation of already proven, efficacious solutions. The development of implementation research that can help provide some solutions on how this can be achieved is sorely needed

Scalar conservation laws on constant and time-dependent Riemannian manifolds

In this paper we establish well-posedness for scalar conservation laws on closed manifolds M endowed with a constant or a time-dependent Riemannian metric for initial values in L^\infty(M). In particular we show the existence and uniqueness of entropy solutions as well as the L^1 contraction property and a comparison principle for these solutions. Throughout the paper the flux function is allowed to depend on time and to have non-vanishing divergence. Furthermore, we derive estimates of the total variation of the solution for initial values in BV(M), and we give, in the case of a time-independent metric, a simple geometric characterisation of flux functions that give rise to total variation diminishing estimates.Comment: 23 pages, no figure