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The paper provides exact and approximate solutions to the title problems. Time-hardening creep is adopted and the stress dependence is assumed to follow the exponential expression proposed by Soderberg. Even though the exact solutions are easy to work with, some approximate solutions are discussed. These approximate solutions are obtained from the exact ones by simply ignoring certain terms; error

This overview provides a comparative analysis of strategies and visions for the bio-economy. It concentrates on the US, EU, Finland, Germany, Sweden, Canada and Australia. It comments on China, Russia, Brazil and Malaysia. It also briefly outlines the OECD policy agenda for the bio-economy.

In this thesis the evolution and consequences of multiple queen societies (polygyny) in leptothoracine ants are discussed. The majority of the studies have been conducted on the boreal species Leptothorax acervorum, but polygynous behaviour is also discussed in a broader sense concerning ant species in general. In L. acervorum the intra-colony relatedness is high. Relatedness in monogynous colonie

Popular Abstract in Swedish En central frågeställning inom ekologin handlar om hur och varför organismers utbredning och antal varierar i tid och rum. Detta forskningsfält går under namnet populationsdynamik och är ämnet för min avhandling. Populationsdynamik handlar om mönster, slumpmässighet, förändringar; helt enkelt matematik! Av den anledningen är det inte bara önskvärt, utan faktiskt nödvändPopulation dynamics in space and time are manifested as changes in the distribution and abundance of organisms. To couple such patterns to the underlying processes is a central question in ecology and also key to successful management. In this thesis, I use theoretical models as well as time series data to analyze population dynamics in environments that are variable in space or time. An example o

Popular Abstract in Swedish Med dagens medicinska teknik måste mottagare av transplanterade organ ta immundämpande läkemedel varje dag för att undvika att transplantatet avstöts. Dessa patienter får ett generellt nedsatt immunförsvar vilket betyder att de blir mottagliga för infektionssjukdomar, samt har en ökad risk för att utveckla tumörer. När det gäller transplantation av vävnader från andra aInhibition of the costimulatory molecules B7 and CD40L with CTLA4Ig and anti-CD40L administered only during the first week after transplantation induces indefinite survival of allo- and xenogeneic heart transplants and significantly prolongs skin grafts in C3H mice. However, this treatment protocol is not as effective in C57BL/6 mice which reject skin transplants with nearly the same median surviv

Popular Abstract in Swedish Att finna metoder som är snabbare, ger noggrannare resultat och utökar möjligheterna är det övergripande målet för forskningen inom teoretisk kemi. Denna avhandling utgör inget undantag. Sålunda, CI rutiner som möjliggör större beräkningar än tidigare har implementerats i RASSCF modulen i Molcas; nya metoder att lokalisera multipolmomement och polariserbarheter har utveThe method development research in the field of theoretical chemistry is the never ending quest for methods that are faster, gives more accurate results, and expands the possibilities. The work in this thesis is no exception to that statement. Thus a CI routine more suited for calculations on large active spaces was implemented in the RASSCF code of Molcas; a new scheme for localizing multipole mo

Laser spectroscopy techniques can be used for tumour detection as well as for localised therapy of malignancies. Laser-induced fluorescence with or without exogenously administered tumour seeking agents is a promising technique for real-time detection of atypical cells and dysplasia before the diseased areas can be visualised by the naked eye. Tumour borders can also be delineated towards normal n

Massive destruction of flint and stone artefacts by fire has been found at two sites in south-eastern Scania, the southernmost county of Sweden. At the site of Svartskylle, dated to the Early Funnel-Necked Beaker Culture (TRB) at about 3400 cal. BC, fragments showed that several thin-butted flint axeheads as well as a small number of thin-bladed axeheads had been heavily fragmented by fire. During

The high-order harmonics that are created in the interaction between an intense laser pulse (around 10¹⁴ W/cm²) and a gas medium are studied. The high-order harmonic radiation is a relatively new source of coherent radiation in the short wavelength range. The high-order harmonics are interesting for applications because of their good spatial and temporal coherence, their shor

Popular Abstract in Swedish Pelagiska bakterier använder löst organiskt material som kol- och energikälla. Det lösta materialet kan ha sitt ursprung i intern (autokton) eller terrester (allokton) primärproduktion. Den här avhandlingen handlar om hur bakterier använder autoktont och alloktont producerat kol. Dessutom undersöker jag om det finns en koppling mellan kolkällans ursprung och strukturen Organic substrates for pelagic bacteria are derived from dissolved organic carbon (DOC) in the water column that originates either from primary production from within the lake itself (autochthonous), or import of organic matter from the terrestrial watershed (allochthonous production). This thesis addresses the utilization of allochthonous versus autochthonous carbon (C) sources by lake bacteriopl

Measurements and extraction of Q-value and self-resonance frequency of on-chip differential symmetrical inductors have been performed. Both 1-port and 2-port measurements have been carried out. In the 1-port measurements a high frequency broadband 180

Popular Abstract in Swedish Ekologin hos lavdagsvärmaren (Dysauxes ancilla) studerades inom den enda svenska populationen vid Beijershamn på Öland. Populationen utgör en isolerad förekomst på nordgränsen av artens utbredningsområde, som huvudsakligen är mellan- och sydosteuropeiskt. Arten är rödlistad som akut hotad. Resultaten visar att lavdagsvärmaren för närvarande endast förekommer inom ett 4 The ecology of the moth Dysauxes ancilla was studied in the only Swedish breeding area at Beijershamn, situated on the Baltic island of Öland. The population is a northern outpost, separated from the species´ continous distribution area in middle- and southeast Europe. There is a general opinion that there has been a reduction of the species distribution during the last decades, but no studies hav

The interaction between large hydrophobic and hydrophilic surfaces in aqueous solution is investigated, using Metropolis Monte Carlo simulations and density functional theory. Special attention is devoted to the solvation force and its dependence on the nature of the solvent-solvent and solvent-surface interactions. In order to facilitate simulations of surface forces in aqueous systems, methods