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Popular Abstract in Swedish Denna avhandling behandlar design, tillverkning, karakterisering och optimering av elektroniska komponenter alla baserade på kvantmekanisk tunnling. Tunnling är ett rent kvantmekaniskt fenomen utan någon klassisk motsvarighet, som först blir relevant då dimensionerna krymper ner i nanometerskala (en nanometer är en miljarddel's meter). Då kan elektroner ”tunnla” igenomThis thesis concerns different kinds of tunneling based devices all showing negative differential resistance. The thesis is divided in three parts, resonant tunneling transistors, Esaki diodes and coupled zero dimensional systems. The resonant tunneling transistors are GaAs-based vertical field effects transistors, based on a combination of overgrown tungsten gates and double barrier heterostruct

I started with a rather superficial overview of some of the problems that medieval archaeologists have to face when they try to study marginal areas, marginal in the view of those who are living near the political and economic power on one level or another. We can formulate the problems in centre-periphery models but we have also discussed some kind of world system thinking (which of course is con

In Sweden, at least one school fire occurs every day. In most cases, arson is the cause of that fire. The costs for these arson fires are considerable, especially those occurring after school hours. This paper presents data for typical arson fire scenarios in schools and kindergartens in Sweden. This data will later be used to evaluate, with regard to cost and benefit, different active and passive

Cyclooxygenase-2 (COX-2) is an enzyme that has been extensively investigated as a prognostic marker in cancer. In non-small cell lung cancer (NSCLC) previous results regarding the prognostic impact of COX-2 expression are inconsistent. Therefore we evaluated the association between transcript levels and overall survival in nine publicly available gene expression data sets (total n = 1337) and dete

Consumption of oats has long been known to lower plasma total and low-density lipoprotein (LDL) cholesterol levels, an effect usually attributed to the soluble fibers β-glucans. On the basis of this cholesterol-lowering effect, oats are ascribed cardiovascular health-promoting properties. However, besides cholesterol levels, effects of oats on parameters relating to atherosclerosis development hav

How various macromolecules are exchanged between cells and how they gain entry into recipient cells are fundamental questions in cell biology with important implications e.g. non-viral drug delivery, infectious disease, metabolic disorders, and cancer. The role of heparan sulfate proteoglycan (HSPG) as a cell-surface receptor of diverse macromolecular cargo has recently been manifested. Exosomes,

The customary way to determine whether an adopted Supplemental Instruction (SI) program has been successful or not is by comparing course results for two groups, SI attendees and non-attendees. The division of SI attendees and non-attendees is generally done rather arbitrarily by prescribing a minimum number of SI sessions a student has to attend to be considered an SI attendee. Although the SI at

The relation between the self-diffusion coefficient, D-self, of water and the free volume hole size, V-h, has been investigated in a hydroxypropyl methylcellulose (HPMC)-water system in the water content range 0.08-0.36 w/w, at room temperature. Furthermore, the thermal properties of the water in the HPMC-water system, as measured with differential scanning calorimetry (DSC) and the tensile storag

The Greenland ice core from NorthGRIP (NGRIP) contains a proxy climate record across the Pleistocene-Holocene boundary of unprecedented clarity and resolution. Analysis of an array of physical and chemical parameters within the ice enables the base of the Holocene, as reflected in the first signs of climatic warming at the end of the Younger Dryas/Greenland Stadial 1 cold phase, to be located with

Animal flight performance has been studied using models developed for man-made aircraft. For an aeroplane with fixed wings, the energetic cost as a function of flight speed can be expressed in terms of weight, wing span, wing area and body area, where more details are included in proportionality coefficients. Flying animals flap their wings to produce thrust. Adopting the fixed wing flight model i

The first experimental and theoretical evidence of the surface-catalyzed reaction of p,p'-dimercaptoazobenzene (DMAB) produced from para-aminothiophenol (PATP) by local surface plasmons was reported in 2010, and since that time a series of investigations have supported these findings using different experimental and theoretical methods. Recent work has also found that local plasmons can drive a su