We show that the all-spectrum transmission blockage through a low-pass screen is bounded by the static polarizability per unit area of the screen, irrespective of how complicated the materials involved are. The angular dependence at oblique incidence is investigated, and the results are verified by measurements on an array of split ring resonators.

In this thesis computationally intensive methods are used to estimate models and to make inference for large, spatio-temporal data sets. The thesis is divided into two parts: the first two papers are concerned with video analysis, while the last three papers model and investigate environmental data from the Sahel area in northern Africa. In the first part of the thesis, mixture models are used to

An open European market for goods and services, including transport services, stimulates trade, global competitiveness and economic growth. At the same time, concerns about domestic job security and the environment have sparked debate. This report should be considered a first modest contribution to a mainly unexplored area in the past. Cabotagestudien consists of a walkthrough of previous research

A low power wideband low noise amplifier (LNA) was designed and implemented in SiGe HBT technology. The measured noise figure is less than or equal to 1 dB in almost the entire L-band. The gain in the L-band is above 13 dB with a gain variation of 4 dB. Hence, it’s useful for present as well as future GNSS applications. The current consumption is 5 mA from a single supply of +5V. The stability of

Popular Abstract in English Plants produce an array of organic chemicals with an enormous diversity of structural types. Many of these phytochemicals are biologically active compounds necessary for the well-being, survival, and evolution of the plants, but also have been used by humans, who have used them in traditional medicine and for pharmaceutical industry. During the course of this research, Nature has been recognized as a rich source of potentially useful chemicals. Throughout the years, phytochemical studies have led to the discovery of an enormous number of natural products, their chemical diversity is unique and many of them possess various biological activities. As a contribution, this thesis presents the results obtained from the phytochemical study of four Bolivian plants. Sene

In the present work amphiphilic graft copolymers were prepared by free radical copolymerization of macromonomers in solution. The graft copolymers consisted of methacrylate backbones bearing ethylene oxide (EO)n side chains of varying length as ionophilic groups, and fluorocarbon (CF2)6 side chains or hydrocarbon groups as ionophobic groups. Homogenous polymer gel electrolytes were prepared by add

Short essay on Howard Hawks' Scarface: Shame of a Nation (1932)

Popular Abstract in Swedish Informationsteknologin utvecklas i allt snabbare takt. Däremot tycks utvecklingen ske långsammare när det gäller de modeller, metaforer och metoder som används för att beskriva och förstå hur information sprids och hanteras i organisationer, i kommuner och i samhället i stort. Använder vi egentligen IT på ett effektivt sätt i det dagliga arbetet? I den här avhandlingen New information technology is developing faster than the models, metaphors and methods in use for conceptualizing the sharing and managing of information in organizations, in communities and in society in general. The way we utilize information technology today does not seem to succeed in supporting the everyday work practices through which organizations accomplish their work. In this Ph.D. disser

Hur kan det komma sig att en relativt stor andel lärare på en och samma gång är missnöjda med en rad arbetsvillkor och upplever att arbetet är meningsfullt? Varför är, med andra ord, många lärare nöjda med sin yrkesutövning som lärare samtidigt som de är missnöjda som anställda? Frågeställningarna har attackerats från flera håll med utgångspunkt från läraryrkets och skolans utveckling under de sen

Popular Abstract in Swedish Bakgrund Streptococcus pyogenes, eller grupp A streptokocker, är en av de vanligaste sjukdomsframkallande bakterierna hos människan. De orsakar ofta relativt harmlösa och lättbehandlade ytliga infektioner i hals (halsfluss) och hud (svinkoppor) men kan också ge djupare och livshotande infektioner. Dessutom förekommer följdsjukdomar efter infektioner med grupp A streptoPathogenic bacteria often produce potent proteases capable of destroying host tissue thereby providing the bacteria with tools for spreading and nutrient access. This thesis describes how group A, C and G streptococci can acquire surface bound protease activity through an alternative mechanism, namely by binding and activation of the human protease precursor plasminogen. Group A streptococci of c