Sökresultat

A prerequisite for the design and evaluation of wireless systems is the understanding of propagation channels. While abundant propagation knowledge exists for bands below 6 GHz, the same is not true for millimeter-wave frequencies. In this paper, we present the design, implementation and measurement-based verification of a re-configurable 27.5-29.5 GHz channel sounder. Based on the switched array

Two-dimensional (2D) topological insulators have fascinating physical properties which are promising for applications within spintronics. In order to realize spintronic devices working at room temperature, materials with a large nontrivial gap are needed. Bismuthene, a 2D layer of Bi atoms in a honeycomb structure, has recently attracted strong attention because of its record-large nontrivial gap,

Soil organic matter (SOM) supports the Earth's ability to sustain terrestrial ecosystems, provide food and fiber, and retains the largest pool of actively cycling carbon. Over 75% of the soil organic carbon (SOC) in the top meter of soil is directly affected by human land use. Large land areas have lost SOC as a result of land use practices, yet there are compensatory opportunities to enhance prod

Twenty Apolipoprotein A-I (ApoA-I) variants are responsible for a systemic hereditary amyloidosis in which protein fibrils can accumulate in different organs, leading to their failure. Several ApoA-I amyloidogenic mutations are also associated with hypoalphalipoproteinemia, low ApoA-I and high-density lipoprotein (HDL)-cholesterol plasma levels; however, subjects affected by ApoA-I-related amyloid

During the winter and spring of 2006, Denmark and Scandinavia faced its most serious crisis since World War II. The conflict started as a Danish newspaper published a number of cartoons, some of which portrayed the prophet Muhammad. After the Danish government rejected their requests to censor the media, Danish Islamists distributed these pictures to some senior political and religious figures in

Sweden is a diverse and multilingual place. Today’s students represent a broad spectrum of cultural, linguistic, and socioeconomic backgrounds. Sweden is also a site for mobility as people flow in and out through processes of migration, tourism, international trade, and study abroad. It is in this context that English is taught in Swedish upper secondary schools. The subject of English in Sweden,

Sedan mitten på 1900 talet har halvledarmaterial revolutionerat hur vi ser på världen genom uppfinningar som det har gett upphov till, såsom datorer, solceller, och lysdioder. Det är möjligheten att kunna styra halvledarens förmåga att leda ström—mellan att vara nästan metallisk till att vara isolerande—som gör den användbar för tillämpningar inom elektronik. Under de senaste decennierna har elektThis dissertation focus on the atomic-scale characterization of the surface properties and electronic structure of III–V semiconductor nanowires (NWs). Since the early 2000s, the fabrication and characterization of III–V NWs has been a very significant topic within material science due to their potential for applications in lighting, energy harvesting, and electronics. A prominent feature of the N

The paper addresses the theoretical concept and methodological usefulness of 'lay theories' for conducting comparative research. 'Lay knowledge' is a well-researched concept particularly in medicine and health (e.g. Williams & Popay 2006), even if often regarded as an 'obstacle' that needs to be overcome in order to spread 'proper' scientific, medical knowledge. Critical studies within medicin

The third sector of national innovation systems comprises non-academic, publicly owned R&D organizations that complement universities and private-sector firms and are normally called ‘research institutes’. Scholarly attention to these organizations has been scarce, partly a consequence of the theoretical imbalance in favor of conceptualizations of innovation processes as requiring mainly unive

Experimental studies on protein dynamics at atomic resolution by NMR-spectroscopy in solution require isolated 1H-X spin pairs. This is the default scenario in standard 1H-15N backbone experiments. Side chain dynamic experiments, which allow to study specific local processes like proton-transfer, or tautomerization, require isolated 1H-13C sites which must be produced by site-selective 13C labelin

Mining, seen as a source of revenue in most developing countries, threatens seriously the environment. Mining impacts the water quality and one of the main problems of mining is acid mine drainage. Low pH and high concentration of heavy metals characterize acid mine drainage. When a stream is impacted by acid mine drainage both human activities and the ecological system are seriously affected. In

Recent emission legislation in the marine sector has emphasized the need to reduce nitrogen oxides (NOx) emissions as well as sulphur emissions. The fulfilment of emission legislation limits with conventional marine diesel oil (MDO) requires complex and expensive aftertreatment systems and in this framework lean burn pilot ignited dual fuel (diesel and natural gas) is revealed as one of the most s

Much scientific evidence indicates that the Earth's climate is changing and the world has become more concerned about the global climate. This has encouraged many countries to consider future clean power production with wind power taking an increasing part. In Sweden, the government declared the intention of generating 30 TWh/year from the wind by 2020 instead of 7.1 TWh/year achieved in 2012. Egy

Biogas production from wheat straw is one strategy of converting biomass to bioenergy, but pretreatment of the lignocellulosic material is necessary in order to render the substrate biodegradable. In this study, four different mechanical pretreatments of wheat straw were investigated: roll milling, extrusion, pelletization, and hammer milling. The effects of the pretreatments on anaerobic digestio

Analyzing genomic data across populations is central to understanding the role of genetic factors in health and disease. Successful data sharing relies on public support, which requires attention to whether people around the world are willing to donate their data that are then subsequently shared with others for research. However, studies of such public perceptions are geographically limited and d

Diverse organisms use Earth's magnetic field as a cue in orientation and navigation. Nevertheless, eliciting magnetic orientation responses reliably, either in laboratory or natural settings, is often difficult. Many species appear to preferentially exploit non-magnetic cues if they are available, suggesting that the magnetic sense often serves as a redundant or 'backup' source of information. Thi

Purpose: To assess the performance of activities of daily living (ADL) in individuals with moderate to severe multiple sclerosis (MS). Method: A total of 12 men and 32 women with MS ( Expanded Disability Status Scale, EDSS, 6.0-8.5) were studied. The performance of personal ADL (P-ADL) and instrumental ADL (I-ADL) was assessed with the Functional Independence Measure (FIM) and the Assessment of Mo

Light detection and ranging (LIDAR) experiments are normally pursued for range resolved atmospheric gas measurements or for analysis of solid target surfaces using fluorescence of laser-induced breakdown spectroscopy. In contrast, we now demonstrate the monitoring of free gas enclosed in pores of materials, subject to impinging laser radiation, employing the photons emerging back to the surface la

An experiment was conducted to follow the fate of the cyanobacterial toxin, nodularin, produced by Nodularia spumigena through ingestion by Mytilus edulis and re-ingestion of faecal material (coprophagy). Mussels were fed with cultures of N. spumigena, and the faeces that were produced were fed to other mussels not previously exposed to N. spumigena. Concentrations of nodularin were measured in th

Mercury is a hazardous environmental pollutant mobilized from natural sources, and anthropogenically contaminated and disturbed areas. Current methods to assess mobility and environmental impact are mainly based on field measurements, soil monitoring, and kinetic modelling. In order to understand in detail the extent to which different mineral sources can give rise to mercury release it is necessa