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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

Identification and isolation of cardiomyocytes from the heart, embryonic stem cells, or induced pluripotent stem cells is a challenging task and will require specific isolation techniques. Less than 30% of the cells within the murine heart are cardiomyocytes and, what is more, there are multiple sub-populations of cardiomyocytes like atrial, ventricular and conduction system cardiomyocytes. In Pap

For meeting stringent emission restrictions, a modern solution is to operate in or close to the flameless mode. It implies a copious dilution of the reactants with vitiated gas resulting in low oxidant or fuel concentration and consequently low volumetric heat-release rate. On the contrary to traditional flames where heat release is occurring in very thin fronts, the flameless operation lies in th

Hydrogen normally occurs as hydroxyl ions related to defects at specific crystallographic sites in the structures, and is normally characterized by infrared spectroscopy (FTIR). For quantification purposes the FTIR technique has proven to be less precise since calibrations against independent methods are needed. Hydrogen analysis by the NMP technique can solve many of the problems, due to the low

In February 2007, an epidemic of severe dermatitis from Chinese recliner chairs and sofas started to unfold first in Finland and a few months later in the UK. Some patients reacted in patch tests (PTs) strongly to the material of their furniture, either leather or fabric. There have been hundreds of reports of chair or sofa dermatitis from Finland and the UK, with all cases linked to the same furn

Atmospheric ions participate in the formation of new atmospheric aerosol particles, yet their exact role in this process has remained unclear. Here we derive a new simple parameterization for ion-induced nucleation or, more precisely, for the formation rate of charged 2-nm particles. The parameterization is semi-empirical in the sense that it is based on comprehensive results of one-year-long atmo

High levels of the triacylglycerol-rich lipoproteins, very low density lipoprotein (VLDL) and intermediate density lipoprotein (IDL) have been identified as independent risk factors for coronary heart disease, and inflammation is thought to contribute to atherosclerosis and its complications. To understand how dyslipidemia promotes inflammation, we have characterised the effects of VLDL treatment

Early erythroblasts from patients with refractory anemia (RA) and RA with ringed sideroblasts (RARS) show constitutive mitochondrial release of cytochrome c. Moreover, mature erythroblasts in RARS, but not in RA, display aberrant accumulation of mitochondrial ferritin (MtF). We analyzed cytochrome c release, MtF expression, and gene expression during erythrold differentiation in bone marrow cells

Even though there has been a rapid development in instrumentation and applications of supercritical fluid chromatography (SFC), relatively little is known about retention mechanisms compared to high-performance liquid chromatography (HPLC). Much effort has been made to characterize the influence of injection solvents on chromatographic efficiency in HPLC, however has been left rather uninvestigate

A detailed study has been made of soot growth in two premixed flat ethylene/air flames, at I broken vertical bar = 2.1 and I broken vertical bar = 2.3, where focus has been on following the change in optical properties from nascent to more mature soot, and the importance of these properties for laser-induced incandescence (LII). A combination of two-color LII (2C-LII) and elastic light scattering

Evolutionary processes can complicate conservation efforts for species with uncertain taxonomic classifications and discrete geographic populations. Discordant morphological and genetic patterns across the geographic range of species further calls for the identification of evolutionary significant units for conservation. Using island and mainland populations of a small Australian passerine (the su

REMO-HAM is a new regional aerosol-climate model. It is based on the REMO regional climate model and includes most of the major aerosol processes. The structure for aerosol is similar to the global aerosol-climate model ECHAM5-HAM, for example the aerosol module HAM is coupled with a two-moment stratiform cloud scheme. On the other hand, REMO-HAM does not include an online coupled aerosol-radiatio

Fast substitution of chloride for bromide and iodide trans to triphenylsilyl in trans-PtCl(SiPh3)(PMe2Ph)2 has been studied by stopped-flow spectrophotometry in acetonitrile solution. Substitution is reversible with an observable solvent path via the solvento complex trans-[Pt(SiPh3)(MeCN)(PMe2Ph)2]+, which has also been synthesized and characterized in solution. Rate constants for the forward and

Objective: The auditory brainstem response (ABR) is often affected in neurodevelopmental disorders. The aim of this study was to investigate gender differences in ABR between young females and young males with ADHD, compared to control subjects. Method: We studied 63 females with ADHD (mean 13.8 years), 26 female controls (mean 13.8years), 48 males with ADHD (mean 13.1 years), and 20 male controls

The social determinants of health form a complex and dynamic web, shaping both populationand individual health and disease. The built environment and especially human dwellingsinfluence health in many ways. Associations between factors such as dampness, mouldgrowth, heating/insulation, and crowding on the one hand and respiratory health andinfectious diseases on the other hand have been studied in

A semistructured personal interview was performed with 29 carriers of hemophilia A or B, 1-5 years after a pregnancy in which prenatal diagnosis (PND) was performed by fetal blood sampling. Fetal blood sampling by fetoscopy was significantly more often reported by the women to the more trying than expected than was ultrasound-guided heart puncture. Of 29 women 13 was classified as having experienc

Foot problems complicating diabetes are a source of major patient suffering and societal costs. To prevent, or at least reduce, the adverse effects of foot problems in diabetes, the International Working Group on the Diabetic Foot (IWGDF; www.iwgdf.org) was founded in 1996, consisting of experts from almost all the disciplines involved in the care of patients with diabetes and foot problems. An im

Floral volatile benzenoid/phenylpropanoid (FVBP) biosynthesis is a complex and coordinate cellular process executed by petal limb cells of a Petunia×hybrida cv. 'Mitchell Diploid' (MD) plant. In MD flowers, the majority of benzenoid volatile compounds are derived from a core phenylpropanoid pathway intermediate by a coenzyme A (CoA) dependent, β-oxidative scheme. Metabolic flux analysis, reverse g

The load capacity of long adhesive lap joints is often governed by stress concentrations at the lap ends. This paper investigates a method to minimize these stress concentrations by using a bond line with low shear stiffness and sufficient strength, here denoted as a resilient bond line. The resilient bond line is intended to increase the load carrying capacity of long lap joints by achieving a mo