The problem of spontaneous evolution of morphological patterns in thin (,100 nm) unstable liquid films on homogeneous solid substrates is resolved based on a 3D nonlinear equation of motion. Initially, a small amplitude bicontinuous structure emerges, which either grows and fragments into a collection of microdroplets (for relatively thinner films), or leads directly to isolated circular holes (for thicker films) which dewet the surface. The characteristics of a pattern, and its pathway of evolution, thus depend crucially on the form of the intermolecular potential in an extended neighborhood of the initial thickness. The linear and 2D nonlinear analyses used hitherto fail completely in prediction of morphological patterns, but can predict their length scales rather well. [S0031-9007(98)07349-9] PACS numbers: 68.15. + e, 47.20.Ma, 47.54. + r, The problem of stability and spontaneous pattern formation in thin (,100 nm) fluid films is central to a host of technological applications (e.g., coatings) and to a diversity of physical and biological thin film phenomena (e.g., wetting, adhesion, colloids, membrane morphology).Like all spinodal processes (e.g., phase separation of incompatible materials), the free surface of an initially uniform thin film becomes unstable and deforms spontaneously to engender a microstructure when the second derivative of the excess intermolecular free energy (per unit area) with respect to the (local) film thickness is negative, viz., ≠ 2 DG͞≠h 2 , 0 [1-4]. Thin film experiments show a variety of microstructures [5][6][7][8][9][10][11] ranging from microdroplets to holes, as well as a spectrum of bicontinuous structures. However, our current theoretical understanding of thin film patterns and their relationship to the surface properties/intermolecular interactions is very rudimentary, and even misleading, since it is based largely on the linear stability analysis [1,2], which, e.g., excludes the possibility of circular holes. The 2D nonlinear simulations [3,4] also cannot provide a clue regarding the full 3D morphology of an unstable thin film. The purpose of this Letter is to uncover the variety of morphological patterns which can form spontaneously in an unstable film, and the conditions for the selection of a particular pattern. Complete 3D nonlinear simulations for the first time provide a formalism for correlating the film morphology with the interfacial interactions and the film thickness, and make it possible to directly compare theory and experiments. Among other things, such a formalism will also help address the inverse problem of characterization of surface interactions from the observed morphology.For simulations, we consider a fairly general excess intermolecular interaction free energy composed of antagonistic (attractive/repulsive) long and (relatively) short range interactions [4,12].When the van der Waals component of the substrate surface tension exceeds that of the film material, the effective Hamaker constant A is negative [4,12], signifying a long range apolar van der...

Background:Rhesus (Rh) disease and extreme hyperbilirubinemia (EHB) result in neonatal mortality and long-term neurodevelopmental impairment, yet there are no estimates of their burden.Methods:Systematic reviews and meta-analyses were undertaken of national prevalence, mortality, and kernicterus due to Rh disease and EHB. We applied a compartmental model to estimate neonatal survivors and impairment cases for 2010.Results:Twenty-four million (18% of 134 million live births ≥32 wk gestational age from 184 countries; uncertainty range: 23–26 million) were at risk for neonatal hyperbilirubinemia-related adverse outcomes. Of these, 480,700 (0.36%) had either Rh disease (373,300; uncertainty range: 271,800–477,500) or developed EHB from other causes (107,400; uncertainty range: 57,000–131,000), with a 24% risk for death (114,100; uncertainty range: 59,700–172,000), 13% for kernicterus (75,400), and 11% for stillbirths. Three-quarters of mortality occurred in sub-Saharan Africa and South Asia. Kernicterus with Rh disease ranged from 38, 28, 28, and 25/100,000 live births for Eastern Europe/Central Asian, sub-Saharan African, South Asian, and Latin American regions, respectively. More than 83% of survivors with kernicterus had one or more impairments.Conclusion:Failure to prevent Rh sensitization and manage neonatal hyperbilirubinemia results in 114,100 avoidable neonatal deaths and many children grow up with disabilities. Proven solutions remain underused, especially in low-income countries.

Dispersion forces are present everywhere. Their importance, however, is largely neglected because directly at a surface or at an interface they are mostly weak compared with specific interaction of short range. Here, we show that these forces are nonetheless extremely relevant and may have drastic consequences on the stability of thin films. We demonstrate that a force (per unit area) of <1 Pa is capable of “destroying” 100 nm (!) thick films, even if they are “glued” to the substrate by end-grafted polymers. We present the temporal evolution of different morphologies of unstable thin liquid polymer films caused by destabilizing intermolecular forces.

Health systems and polices have a critical role in determining the manner in which health services are delivered, utilized and affect health outcomes. ‘Health' being a state subject, despite the issuance of the guidelines by the central government, the final prerogative on implementation of the initiatives on newborn care lies with the states. This article briefly describes the public health structure in the country and traces the evolution of the major health programs and initiatives with a particular focus on newborn health.

We experimentally investigated the retraction of poly(dimethylsiloxane) films of variable thickness on layers of chemically identical molecules, end-grafted onto a silicon substrate (autophobic dewetting of a melt-on-brush system). Measuring simultaneously the dewetted distance (d) and the width (w) of the rim formed by the collection of the retracted liquid, we were able to determine in situ and in real time (t) the contact angle, the velocity of retraction, and the energy dissipation mechanism at the melt-brush interface. The dewetting velocity decreased linearly with the width of the rim. Together with the characteristic thickness dependence and an exponent R of 2 /3 for the power-law behavior of d ∼ t R , we concluded that the melt is slipping on the brush. The slippage length was on the order of 10 µm, indicating little interpenetration between melt and brush. We demonstrate that dewetting experiments represent a valuable tool for the characterization of static and kinetic properties of polymer-polymer interfaces. LA000088U

The effect of electric fields on the rupture of thin viscous films by van der Waals forces Phys. Fluids 15, 641 (2003); 10.1063/1.1538250Self-organized structures in thin liquid films on chemically heterogeneous substrates: Effect of antagonistic short and long range interactions

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We investigated experimentally the morphological evolution of thin polydimethylsiloxane films sandwiched between a silicon wafer and different bounding liquids with interfacial tensions varying by 2 orders of magnitude. It is shown that increasing the compatibility between film and bounding liquid by adding a few surfactant molecules results in a faster instability of shorter characteristic wavelength. Inversely, based on the characteristic parameters describing the instability we determined extremely small interfacial tensions with a remarkable accuracy.