Space-time diagrammatics

We introduce a new class of two-dimensional diagrams, the \emph{projection diagrams}, as a tool to visualize the global structure of space-times. We construct the diagrams for several metrics of interest, including the Kerr-Newman - (anti) de Sitter family, with or without cosmological constant, and the Emparan-Reall black rings.Comment: 41 pages, minor changes and correction

Integrating actin and myosin II in a viscous model for cell migration

This article presents a mathematical and computational model for cell migration that couples a system of reaction-advection-diffusion equations describing the bio-molecular interactions between F-actin and myosin II to a force balance equation describing the structural mechanics of the actin-myosin network. In eukaryotic cells, cell migration is largely powered by a system of actin and myosin dynamics. We formulate the model equations on a two-dimensional cellular migrating evolving domain to take into account the convective and dilution terms for the biochemical reaction-diffusion equations, with hypothetically proposed reaction-kinetics. We employ the evolving finite element method to compute approximate numerical solutions of the coupled biomechanical model in two dimensions. Numerical experiments exhibit cell polarization through symmetry breaking which are driven by the F-actin and myosin II. This conceptual hypothetical proof-of-concept framework set premises for studying experimentally-driven actin-myosin reaction-kinetic network interactions with generalizations to multi-dimensions

Determination of fungal activity in modified wood by means of micro-calorimetry and determination of total esterase activity

Beech and pine wood blocks were treated with 1,3-dimethylol-4,5-dihydroxyethylen urea (DMDHEU) to increasing weight percent gains (WPG). The resistance of the treated specimens against Trametes versicolor and Coniophora puteana, determined as mass loss, increased with increasing WPG of DMDHEU. Metabolic activity of the fungi in the wood blocks was assessed as total esterase activity (TEA) based on the hydrolysis of fluorescein diacetate and as heat or energy production determined by isothermal micro-calorimetry. Both methods revealed that the fungal activity was related with the WPG and the mass loss caused by the fungi. Still, fungal activity was detected even in wood blocks of the highest WPG and showed that the treatment was not toxic to the fungi. Energy production showed a higher consistency with the mass loss after decay than TEA; higher mass loss was more stringently reflected by higher heat production rate. Heat production did not proceed linearly, possibly due to the inhibition of fungal activity by an excess of carbon dioxide

"Northern Lights and bears and icebergs and everything"

Die Publikation von Edward Saids Monographie Orientalismus hat in der Wissenschaft zu nachhaltigen Diskussionen geführt. Inzwischen ist es weitgehend anerkannt, dass Diskurse über eine Region mit Machtausübung über dieses Gebiet einhergehen. Das trifft auch auf die Arktis zu, eine Region, der in den letzten Jahren vermehrte Aufmerksamkeit zuteilwurde und welche ein wiederkehrender Handlungsort in Philip Pullmans His Dark Materials Trilogie ist. Um einen besseren Einblick in aktuelle Arktisbilder und ihre Tragweite zu erhalten, werden Diskurse zu arktischer Entdeckung, Wissenschaft und Klimawandel in Pullmans Romanen analysiert. Das Konzept des Arktizismus, welches in Analogie zu Saids Orientalismus vorgeschlagen wurde, wird angewendet, um von der Trilogie aufgegriffene Stereotype offen zu legen und Gegenentwürfe zu arktizistischen Bildern im Werk zu lokalisieren.The publication of Edward Said’s monography Orientalism has led to intense discussion among researchers. Today, it is widely accepted knowledge that discourses pertaining to a region can have considerable influence on the region. This is also true for images of the Arctic, a region that has attracted considerable attention in recent years and is a recurring location in Philip Pullman’s His Dark Materials trilogy. To gain a better understanding of contemporary conceptions of the Arctic and their implications, discourses of Arctic exploration, science, and climate change are analysed in Pullman’s novels. The concept of Arcticism, which has been suggested in analogy to Said’s Orientalism, is used to uncover stereotypical images of the Arctic that are repeated in the trilogy. Furthermore, ideas that question Arcticist notions are located in the text

Deploying Renewables in Southeast Asia: Trends and potentials

This paper is part of the IEA ongoing analysis of global renewable energy markets and policies. It focuses on six Southeast Asian countries: Indonesia, Malaysia, the Philippines, Singapore, Thailand, and Vietnam. The report investigates the potentials and barriers for scaling up market penetration of renewable energy technologies in the electricity, heating and transport sectors in the six countries. In addition to analysing the implications of effective policies on renewable energy market growth, it examines how to overcome economic and non-economic barriers that slow investment in renewable energy, and offers policy recommendations to encourage effective and efficient exploitation of renewable energy in Southeast Asia.