1,890 research outputs found

    Non-continuous Froude number scaling for the closure depth of a cylindrical cavity

    Get PDF
    A long, smooth cylinder is dragged through a water surface to create a cavity with an initially cylindrical shape. This surface void then collapses due to the hydrostatic pressure, leading to a rapid and axisymmetric pinch-off in a single point. Surprisingly, the depth at which this pinch-off takes place does not follow the expected Froude1/3^{1/3} power-law. Instead, it displays two distinct scaling regimes separated by discrete jumps, both in experiment and in numerical simulations (employing a boundary integral code). We quantitatively explain the above behavior as a capillary waves effect. These waves are created when the top of the cylinder passes the water surface. Our work thus gives further evidence for the non-universality of the void collapse

    Sudden Collapse of a Granular Cluster

    Get PDF
    Single clusters in a vibro-fluidized granular gas in N connected compartments become unstable at strong shaking. They are experimentally shown to collapse very abruptly. The observed cluster lifetime (as a function of the driving intensity) is analytically calculated within a flux model, making use of the self-similarity of the process. After collapse, the cluster diffuses out into the uniform distribution in a self-similar way, with an anomalous diffusion exponent 1/3.Comment: 4 pages, 4 figures. Figure quality has been reduced in order to decrease file-siz

    Acting on an environmental health disaster: the case of the Aral Sea.

    Get PDF
    The Aral Sea area in Central Asia has been encountering one of the world's greatest environmental disasters for more than 15 years. During that time, despite many assessments and millions of dollars spent by large, multinational organizations, little has changed. The 5 million people living in this neglected and virtually unknown part of the world are suffering not only from an environmental catastrophe that has no easy solutions but also from a litany of health problems. The region is often dismissed as a chronic problem where nothing positive can be achieved. Within this complicated context, Medecins Sans Frontieres, winner of the Nobel Peace Prize in 1999, is actively trying to assess the impact of the environmental disaster on human health to help the people who live in the Aral Sea area cope with their environment. Medecins Sans Frontieres has combined a direct medical program to improve the health of the population while conducting operational research to gain a better understanding of the relationship between the environmental disaster and human health outcomes. In this paper we explore the health situation of the region and the broader policy context in which it is situated, and present some ideas that could potentially be applied to many other places in the world that are caught up in environmental and human health disasters

    Relapsing hepatitis due to cytomegalovirus?

    Get PDF
    Item does not contain fulltex

    Suspension cultures of mononuclear phagocytes in the Teflon culture bag

    Get PDF
    Contains fulltext : 4302.pdf (publisher's version ) (Open Access

    Bifurcation Diagram for Compartmentalized Granular Gases

    Get PDF
    The bifurcation diagram for a vibro-fluidized granular gas in N connected compartments is constructed and discussed. At vigorous driving, the uniform distribution (in which the gas is equi-partitioned over the compartments) is stable. But when the driving intensity is decreased this uniform distribution becomes unstable and gives way to a clustered state. For the simplest case, N=2, this transition takes place via a pitchfork bifurcation but for all N>2 the transition involves saddle-node bifurcations. The associated hysteresis becomes more and more pronounced for growing N. In the bifurcation diagram, apart from the uniform and the one-peaked distributions, also a number of multi-peaked solutions occur. These are transient states. Their physical relevance is discussed in the context of a stability analysis.Comment: Phys. Rev. E, in press. Figure quality has been reduced in order to decrease file-siz

    Duurzaam behandelen in de verslavingszorg:Vandaag werken aan een betere toekomst voor de volgende generatie

    Get PDF
    How do we keep healthcare affordable and at the same time feasible? Will there besufficient finance, and enough people to offer care? With these issues often thetheme of sustainable care comes forward. Sustainable care is often interpreted ascare that promotes the health of citizens, that maintains the high quality of care andimprove where possible, and at the same time highlighting the cost of care.This applies to the care for addicts in the Netherlands no different. Also within theaddiction care we are looking for sustainable solutions. Under sustainable we meanprograms that work: promoting healing, supporting the recovery process andthereby preventing relapses. Sustainability also means it delivers more than justindividual welfare. Here we can think of the social impact, inconvenience andinsecurity, but also to the next generation. Especially on this last topic this articlefocuses. What is needed to work more sustainable and treat the addiction with aneye and focus on the next generation? This is about transgenerational transmissionof addiction: the addiction is passed from (grand) parent to child.To further develop sustainability in the care for addiction is to get a clear picture ofthe children of addicted parents. There should be more attention to early detectionof the possible dependence of older (and possibly child). In addition, attentionshould be to educate and make the timely discussion of the risks and possibleexisting education problem
    corecore