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Let be a compact manifold without boundary whose first homology is nontrivial. The Hodge decomposition of the incompressible Euler equation in terms of 1-forms yields a coupled PDE-ODE system. The -orthogonal components are a "pure" vorticity flow and a potential flow (harmonic, with the dimension of the homology). In this paper we focus on point vortices on a compact Riemann surface without boundary of genus , with a metric chosen in the conformal class. The phase space has finite dimension . We compute a surface of section for the motion of a single vortex () on a torus () with a nonflat metric that shows typical features of nonintegrable 2 degrees of freedom Hamiltonians. In contradistinction, for flat tori the harmonic part is constant. Next, we turn to hyperbolic surfaces () having constant curvature , with discrete symmetries. Fixed points of involutions yield vortex crystals in the Poincaré disk. Finally, we consider multiply connected planar domains. The image method due to Green and Thomson is viewed in the Schottky double. The Kirchhoff – Routh Hamiltonian given in C. C. Lin's celebrated theorem is recovered by Marsden – Weinstein reduction from to . The relation between the electrostatic Green function and the hydrodynamic Green function is clarified. A number of questions are suggested. [ABSTRACT FROM AUTHOR]

This paper presents several arguments for applying a relative poverty line to urban China. For example between 2002 and 2013 urban residents in China changed their assessment of how much money that is necessary. Data from the China Household Income Project indicate that while, assessed against an absolute poverty line, poverty among Chinese urban residents was already fairly low in 2007, increasing proportions fell under a relative poverty line from 1988 to 2007. Thus income growth in urban China was more rapid in the middle segments of the income distribution that at it's lower segments. In 2013, at least as large fractions of the urban population as in many rich countries were deemed poor in relative terms. We also specify and estimate logit models for 2002 and 2013 after first having divided the samples into children, adults and elderly people. We find that the risk of being relative poor in urban China both years under study was positively associated with lack of work among adult household members, a low education of the household head, living in a low-income city, the number of children, and being aged and not receiving a pension. Pensions for the aged in combination with co-residency with adult children or with other adults have kept poverty rates among the increasing number of elderly in urban China from exceeding those among adults. In contrast, relative poverty rates are somewhat higher among children than among the entire urban population. [ABSTRACT FROM AUTHOR]

Introduction: Inflammation is an important risk-associated component of many diseases and can be diagnosed by molecular imaging of specific molecules. The aim of this study was to evaluate the possibility of targeting adhesion molecules on inflammation-activated endothelial cells and macrophages using an innovative multimodal polyvinyl alcohol-based microbubble (MB) contrast agent developed for diagnostic use in ultrasound, magnetic resonance, and nuclear imaging.Methods: We assessed the binding efficiency of antibody-conjugated multimodal contrast to inflamed murine or human endothelial cells (ECs), and to peritoneal macrophages isolated from rats with peritonitis, utilizing the fluorescence characteristics of the MBs. Single-photon emission tomography (SPECT) was used to illustrate 99mTc-labeled MB targeting and distribution in an experimental in vivo model of inflammation.Results: Flow cytometry and confocal microscopy showed that binding of antibody-targeted MBs to the adhesion molecules ICAM-1, VCAM-1, or E-selectin, expressed on cytokine-stimulated ECs, was up to sixfold higher for human and 12-fold higher for mouse ECs, compared with that of non-targeted MBs. Under flow conditions, both VCAM-1- and E-selectin-targeted MBs adhered more firmly to stimulated human ECs than to untreated cells, while VCAM-1-targeted MBs adhered best to stimulated murine ECs. SPECT imaging showed an approximate doubling of signal intensity from the abdomen of rats with peritonitis, compared with healthy controls, after injection of anti-ICAM-1-MBs.Conclusions: This novel multilayer contrast agent can specifically target adhesion molecules expressed as a result of inflammatory stimuli in vitro, and has potential for use in disease-specific multimodal diagnostics in vivo using antibodies against targets of interest. [ABSTRACT FROM AUTHOR]

For conformal maps defined in the unit disk one can define a certain Poisson bracket that involves the harmonic moments of the image domain. When this bracket is applied to the conformal map itself together with its conformally reflected map the result is identically one. This is called the string equation, and it is closely connected to the governing equation, the Polubarinova-Galin equation, for the evolution of a Hele-Shaw blob of a viscous fluid (or, by another name, Laplacian growth). In the present paper we show that the string equation makes sense and holds for general polynomials. [ABSTRACT FROM AUTHOR]

Cauchy and exponential transforms are characterized, and constructed, as canonical holomorphic sections of certain line bundles on the Riemann sphere defined in terms of the Schwarz function. A well known natural connection between Schwarz reflection and line bundles defined on the Schottky double of a planar domain is briefly discussed in the same context. [ABSTRACT FROM AUTHOR]

This article presents new research on income-based child indicators for immigrant children from 17 different national backgrounds and children of parents born in Sweden observed during the 3-year periods 1983–85, 1995–97 and 2008–10. This research examines mean household income, representation at the top of the income distribution and relative poverty differ for immigrant children from the corresponding levels among children with native born parents. Most of the analysis is concentrated on the second generation of immigrant children. It is shown that the relative position of immigrant children deteriorated between 1983–85 and 1995–97 when the labour market situation of immigrant parents weakened more than among native born parents. Changes thereafter were more complex. Children born in Sweden to parents from Denmark, Norway or Germany were as likely as children of native born parents to be observed at the top of the income distribution in contrast to children of parents from countries with middle or low human development. Poverty rates among immigrant children were higher among all categories of immigrant children in 2008–10 than among children of native born parents. These cross origin differences in income-based child indicators can be attributed to the reasons and qualifications parents had when they entered Sweden and the number of years since their immigration. A majority of children living in Sweden that are classified as poor in 2008–10 were immigrant children of various categories. [ABSTRACT FROM AUTHOR]

Introduction: Both diagnostic ultrasound (US) and magnetic resonance imaging (MRI) accuracy can be improved by using contrast enhancement. For US gas-filled microbubbles (MBs) or silica nanoparticles (SiNPs), and for MRI superparamagnetic or paramagnetic agents, contribute to this. However, interactions of MBs with the vascular wall and cells are not fully known for all contrast media. Methods: We studied the in vitro interactions between three types of non-targeted air-filled MBs with a polyvinyl-alcohol shell and murine macrophages or endothelial cells. The three MB types were plain MBs and two types that were labelled (internally and externally) with superparamagnetic iron oxide nanoparticles (SPIONs) for US/MRI bimodality. Cells were incubated with MBs and imaged by microscopy to evaluate uptake and adhesion. Interactions were quantified and the MB internalization was confirmed by fluorescence quenching of non-internalized MBs. Results: Macrophages internalized each MB type within different time frames: plain MBs 6 h, externally labelled MBs 25 min and internally labelled MBs 2 h. An average of 0.14 externally labelled MBs per cell were internalized after 30 min and 1.34 after 2 h; which was 113% more MBs than the number of internalized internally labelled MBs. The macrophages engulfed these three differently modified new MBs at various rate, whereas endothelial cells did not engulf MBs. Conclusions: Polyvinyl-alcohol MBs are not taken up by endothelial cells. The MB uptake by macrophages is promoted by SPION labelling, in particular external such, which may be important for macrophage targeting. [ABSTRACT FROM AUTHOR]

Guanylin ( GUCA2A/ Guca2a/GN) and uroguanylin ( GUCA2B/ Guca2b/UGN) are expressed in the gastrointestinal tract and have been implicated in ion and fluid homeostasis, satiety, abdominal pain, growth and intestinal barrier integrity. Their cellular sources are debated and include goblet cells, entero-/colonocytes, enteroendocrine (EE) cells and tuft cells. We therefore investigated the cellular sources of GN and UGN mRNAs in human and rat duodenal and colonic epithelium with in situ hybridization (ISH) to determine co-expression with Chromogranin A ( CHGA/ Chga/CgA; enterochromaffin [EC] cells), defensin alpha 6 ( DEFA6/ Defa6; Paneth cells), mucin 2 ( MUC2/ Muc2; goblet cells) and selected tuft cell markers. GUCA2A/ Guca2a expression was localized to goblet cells and colonocytes in human and rat colon. In human duodenum, GUCA2A was expressed in Paneth cells and was scarce in villous epithelial cells. In rat duodenum, Guca2a was only localized to goblet cells. Guca2b was focally expressed in rat colon. In human and rat duodenum and in human colon, GUCA2B/ Guca2b was expressed in dispersed solitary epithelial cells, some with a tuft cell-like appearance. Neither GUCA2A nor GUCA2B were co-expressed with CHGA in human duodenal cells. Consequently, EC cells are probably not the major source of human GN or UGN but other EE cells as a source of GN or UGN are not entirely excluded. No convincing overlap with tuft cell markers was found. For the first time, we demonstrate the cellular expression of GUCA2B in human duodenum. The specific cellular distribution of both GN and UGN differs between duodenum and colon and between human and rat intestines. [ABSTRACT FROM AUTHOR]

Disparities in length of schooling between the largest Muslim minority in China, the Hui, and the Han majority are investigated. We use household data collected in Ningxia autonomous region in 2007. It is found that compared with Han persons of the same age and gender, Hui persons have shorter educations with the exception of young and middle-aged urban males who have 12 years of schooling, on average. Particularly noteworthy is that as many as 45 % of adult rural Hui females are not literate. Possible reasons for the shorter educations of Hui in many segments of the population are numerous. We show that the incentive to invest in length of schooling is smaller among Hui than Han as the association between education and income is weaker. We also report that Hui parents spend fewer resources on education than Han parents and that fewer years of schooling for Hui in the first generation helps to explain why Hui persons in the second generation have shorter educations. [ABSTRACT FROM AUTHOR]

It is known that any subharmonic quadrature domain in two dimensions satisfies a natural inner ball condition, in other words there is a specific upper bound on the curvature of the boundary. This result directly applies to free boundaries appearing in obstacle type problems and in Hele-Shaw flow. In the present paper we make partial progress on the corresponding question in higher dimensions. Specifically, we prove the equivalence between several different ways to formulate the inner ball condition, and we compute the Brouwer degree for a geometrically important mapping related to the Schwarz potential of the boundary. The latter gives in particular a new proof in the two dimensional case. [ABSTRACT FROM AUTHOR]

In this paper we represent harmonic moments in the language of transfinite functions, that is projective limits of polynomials in infinitely many variables. We obtain also an explicit formula for the Jacobian of a generalized harmonic moment map. [ABSTRACT FROM AUTHOR]