Sökresultat

Popular Abstract in Swedish ”Har en galopperande häst vid något tillfälle alla hovarna i luften samtidigt?” Den här till synes enkla frågan är inte helt enkel att svara på eftersom det inte går att avgöra med blotta ögat om så är fallet. För att avgöra om hovarna verkligen är i luften på samma gång behöver vi andra redskap med bättre tidsupplösning än våra ögon. Första gången någon lyckades göra eOne objective of attosecond science is to study electron dynamics in atoms and molecular systems on their natural time scale. This can be done using attosecond light pulses. Attosecond pulses are produced in a process called high-order harmonic generation, in which a short, intense laser pulse interacts with atoms or molecules in a highly nonlinear process, leading to the generation of high-order

This paper will continue on the topics presented in previous numbers of Ancient Planet (2012/2; 2012/3) by giving an updated account of the ongoing survey work at Gebel el Silsila in Egypt. However, while previous articles have concerned Graeco-Roman quarry marks and their various meanings, the aim here is to draw attention to the site’s Prehistoric Periods with especial focus on the pictorial rep

To increase indoor coverage for mobile services, we propose a residential small cell infrastructure making use of the existing copper plant. The system is cabinet-based, collocated with VDSL2 and uses small pieces of spectrum next to VDSL2. Inspired by the Ericsson Radio Dot System, it challenges the femtocell paradigm offering full macro functionality in the small cells. An interesting service po

In the Grödinge project pottery was recovered from the five Neolithic sites, totaling c. 280 kg. A selected sample of pottery from four of these sites, i.e. the Eklundshov, Smällan, Kyrktorp and Kvedesta sites, has been studied more closely and also analysed technologically.

A relation between the radiation resistance and the quasi-static polarizability, input capacitance, and input inductance for small electric dipole antennas is investigated. The relation follows from the forward scattering sum rule and sum rules for the input impedance together with resonance models for the partial realized gain and the reflection coefficient.

The Furuta pendulum is used to evaluate a friction compensator based on the dynamic LuGre friction model. The effect of friction compensation is very well illustrated by reduction of limit cycles when stabilising the pendulum. The observer based LuGre friction compensator is compared with classical Coulomb and Stiction compensator schemes. Existing analysis of the LuGre observer is extended to obs

Hjalmarsson (2010) considers an OLS-based estimator of predictive panel regressions that is argued to be mixed normal under very general conditions. In a recent paper, Westerlund et al. (2016) show that while consistent, the estimator is generally not mixed normal, which invalidates standard normal and chi-squared inference. The purpose of the present paper is to study the consequences of this the

Several of the steps in protein synthesis on the ribosome utilize hydrolysis of guanosine triphosphate (GTP) as the driving force. This reaction is catalyzed by translation factors that become activated upon binding to the ribosome. The recently determined crystal structure of an elongation factor-Tu ternary complex bound to the ribosome allows the energetics of GTP activation to be explored by co

Cities typically treat migration and sustainability as separate policy domains. When migration is highlighted in the context of sustainability in urban destination areas, it is typically understood to have no, or at worst, negative impacts on sustainability. As a result, migration and migrants are commonly left out of sustainability policy and planning. Here, we present emerging evidence to refram

α-Synuclein (αSyn) is a neuronal protein predominantly found in the brain, whose native function seems to be associated with vesicle trafficking. While intrinsically disordered in solution, the first ca. 100 residues adopt an amphipathic α-helical structure when the protein adsorbs onto membranes. Additionally, the aggregation of αSyn into highly ordered β-sheet rich amyloid fibrils is associated

 new species can form through hybridization between species. Hybrid speciation in animals has been intensely debated, partly because hard evidence for the process has been difficult to obtain. Here we report the discovery of a European hybrid butterfly lineage, a finding that can be considered surprising given the intense and long-term study of European butterflies. The lineage we describe is main

This dissertation explores the socioeconomic impacts of mine closures in Canada, focusing on the vulnerabilities that arise within local economies and the political economy implications of industrial changes. Through a combination of historical, quantitative, and qualitative analyses, the research provides a comprehensive understanding of the effects of mine closures on employment, municipal finan

The Loess Plateau in China is prone to widespread land degradation (soil erosion, deforestation, and water loss), and therefore, ecological restoration programmes aiming to re-establish the ecosystem by revegetation have been implemented during recent decades. Consequently, a widespread increase in vegetation cover has been reported, but the state and dynamics of forests remain largely unknown. He

We hypothesize that predictable variations in environmental conditions caused by night/day cycles created opportunities and hazards that initiated information dynamics central to life’s origin. Increased daytime temperatures accelerated key chemical reactions but also caused the separation of double-stranded polynucleotides, leading to hydrolysis, particularly of single-stranded RNA. Daytime solar

This essay studies the effect of liquidity on stock returns on the Swedish stock market. Liquidity is addressed both as a market risk factor and an asset characteristics. We use the relative bid-ask spread as a proxy for liquidity level. The aggregate liquidity factor Illiquid-Minus-Liquid is constructed in a similar way to Fama-French SMB and HML factors. Using monthly time-series regressions on

Passenger transport services constitute public utilities, exactly like all the other similar public networks e.g. energy & water distribution, TV broadcasting or postal services. The Member States in the EU have a keen interest in the development of passenger transport and therefore the financing of public transport is such an important economic, political and social issue. In its ideal form,