Half a Century of Kinetic Solar Wind Models

I outline the development of four generations of kinetic models, starting with Chamberlain's solar breeze exospheric model. It is shown why this first kinetic model did not give apposite supersonic evaporation velocities, like early hydrodynamic models of the solar wind. When a self-consistent polarization electric potential distribution is used in the coronal plasma, instead of the Pannekoek-Rosseland's one, supersonic bulk velocities are readily obtained in the second generation of kinetic models. It is outlined how the third and fourth generations of these models have improved the agreement with observations of slow and fast speed solar wind streams.Comment: 10 pages, 3 figures, presented at SW12 conf. ; Copyright (2010 AIP 978-0-7354-0759-6/10) American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics The following article appeared in (CP1216) and may be found at (http://proceedings.aip.org

Revolutionary poetry and liquid crystal chemistry

In the Netherlands, the poet Herman Gorter (1864–1927) is mostly known as the author of the neo-romantic poem _May_ and the “sensitivistic” _Poems_, but internationally he became famous as a propagandist of radical Marxism: the author of influential brochures and of an “open letter” to comrade W.I. Lenin in 1920. During the 1890s, Gorter became increasingly dissatisfied with his poetry, considering it as ego-centric, disinterested and “bourgeois”, unconnected with what was happening in the real (material-political) world. He wanted to put his poetry on a scientific footing, notably by endorsing a dialectical materialist worldview. In the communist society he envisioned, science would become poetry and poetry would become science. In his opus magnum _Pan_ (11,000 lines of verse, published in 1916), two terms are rather prominent, namely _heelal_ (“universe”) and _kristal_ (“crystal”). These signifiers not only reflect important themes, but also two friendships which began around 1900, namely with prominent astronomer and marxist Anton Pannekoek (who studied the universe) and with Ada Prins, the first woman in the Netherlands who acquired a PhD in chemistry, specialised in liquid crystal research. Whereas Ada Prins is mostly remembered as one of Gorter’s secret lovers, she was first and foremost his educated guide into the complex and enigmatic world of twentieth-century chemistry research. Liquid crystal chemistry became an important source of inspiration for Gorter’s work and the main objective of this paper is to demonstrate her influence on Gorter’s _Pan_ as a scientific poem After presenting the two heroes of this paper, and their work in poetry and chemistry respectively, I will analyse the role of liquid crystals in Herman Gorter’s _Pan_, highlighting important connections with Ada Prins’ research into liquid crystal chemistry

Anhedonia and depression severity dissociated by dmPFC resting-state functional connectivity in adolescents

Introduction: Given the heterogeneity within depression, in this study we aim to examine how RSFC in adolescents is related to anhedonia and depression severity on a continuum in line with the RDoC approach. Methods: We examined how RSFC in the dorsal medial prefrontal cortex (dmPFC), nucleus accumbens (NAcc) and pregenual anterior cingulate cortex (pgACC) was related to anhedonia and depression severity in eighty six adolescents (13-21 yrs.). Results: We found both anhedonia and depression severity related to decreased dmPFC RSFC with the precuneus, a part of the default mode network. However we also found that increased dmPFC connectivity with the ACC/paracingulate gyrus related to anhedonia whereas increased RSFC with the frontal pole related to depression severity. Discussion: This work extends the view that the dmPFC is a potential therapeutic target for depression in two ways. 1. We report dmPFC connectivity in adolescents and 2. We show different dmPFC RSFC specific to anhedonia and depression severity, providing neural targets for intervention in young people at risk of depression

Avian chlamydiosis

B

Heart of glass anchors Rasip1 at endothelial cell-cell junctions to support vascular integrity.

Heart of Glass (HEG1), a transmembrane receptor, and Rasip1, an endothelial-specific Rap1-binding protein, are both essential for cardiovascular development. Here we performed a proteomic screen for novel HEG1 interactors and report that HEG1 binds directly to Rasip1. Rasip1 localizes to forming endothelial cell (EC) cell-cell junctions and silencing HEG1 prevents this localization. Conversely, mitochondria-targeted HEG1 relocalizes Rasip1 to mitochondria in cells. The Rasip1-binding site in HEG1 contains a 9 residue sequence, deletion of which abrogates HEG1's ability to recruit Rasip1. HEG1 binds to a central region of Rasip1 and deletion of this domain eliminates Rasip1's ability to bind HEG1, to translocate to EC junctions, to inhibit ROCK activity, and to maintain EC junctional integrity. These studies establish that the binding of HEG1 to Rasip1 mediates Rap1-dependent recruitment of Rasip1 to and stabilization of EC cell-cell junctions