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Density functional theory with hybrid functionals applied to defects in GaAs surfaces: Effect of doping

We have analyzed the influence of a Ga vacancy on electronic properties of GaAs(110) by scanning tunneling microscopy (STM), ab initio electronic structure simulations based on density functional theory with Perdew-Becke-Ernzerhof and Heyd-Scuseria-Ernzerhof functionals and STM simulations. We find that the HSE03 functional improves the description of the band gap of the semiconductor surface in l

Towards a mobile indigeneity? The case of indigenous students from the Chittagong Hill Tracts in Dhaka, Bangladesh

The purpose of this thesis is to examine how increased mobility of indigenous student migrants in Dhaka from the Chittagong Hill Tracts in Bangladesh affects notions of belonging and indigeneity. By applying a theoretical framework of mobility, global interconnectedness and lifestyle, the study challenges representations by indigenous rights advocates of indigenous people as inherently immobile an

Levy Processes with Two-Sided Reflection

Let X be a Levy process and V the reflection at boundaries 0 and b > 0. A number of properties of V are studied, with particular emphasis on the behaviour at the upper boundary b. The process V can be represented as solution of a Skorokhod problem V(t) = V(0)+X(t)+L(t)-U(t) where L, U are the local times (regulators) at the lower and upper barrier. Explicit forms of V in terms of X are surveyed as

A New Route toward Semiconductor Nanospintronics: Highly Mn-Doped GaAs Nanowires Realized by Ion-Implantation under Dynamic Annealing Conditions

We report on highly Mn-doped GaAs nanowires (NWs) of high crystalline quality fabricated by ion beam implantation, a technique that allows doping concentrations beyond the equilibrium solubility limit. We studied two approaches for the preparation of Mn-doped GaAs NWs: First, ion implantation at room temperature with subsequent annealing resulted in polycrystalline NWs and phase segregation of MnA

Asymptotic properties of particle filter-based maximum likelihood estimators for state space models

We study the asymptotic performance of approximate maximum likelihood estimators for state space models obtained via sequential Monte Carlo methods. The state space of the latent Markov chain and the parameter space are assumed to be compact. The approximate estimates are computed by, firstly, running possibly dependent particle filters on a fixed grid in the parameter space, yielding a pointwise

Transport properties of water in hydroxypropyl methylcellulose

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

Crystal Phase Engineering in Single InAs Nanowires.

Achieving phase purity and control in III-V nanowires is a necessity for future nanowire-based device applications. Many works have focused on cleaning specific crystal phases of defects such as twin planes and stacking faults, using parameters such as diameter, temperature, and impurity incorporation. Here we demonstrate an improved method for crystal phase control, where crystal structure variat

TRPA1 mediates spinal antinociception induced by acetaminophen and the cannabinoid Delta(9)-tetrahydrocannabiorcol

TRPA1 is a unique sensor of noxious stimuli and, hence, a potential drug target for analgesics. Here we show that the antinociceptive effects of spinal and systemic administration of acetaminophen (paracetamol) are lost in Trpa1(-/-) mice. The electrophilic metabolites N-acetyl-p-benzoquinoneimine and p-benzoquinone, but not acetaminophen itself, activate mouse and human TRPA1. These metabolites a

The function of cation-binding agents in the enzymatic treatment of municipal sludge.

Treatment of sludge with enzymes has previously been shown to efficiently release organic matter. However, the added enzymes were partially adsorbed to, entrapped by or bound to the sludge structure. Simultaneous decrease of enzymes activities was observed. Reduced adsorption and more effective, lower, enzyme dose was achieved in sludge pre-treated with three cation-binding agents. The enzymatic s

Disentangling the holism of intentional systems from the interactionism of mechanistic systems in person-oriented research

A key assumption in the person-oriented approach is that a person must be understood as a complex, integrated system, represented by patterns of within-person variation rather than scores on separate variables. The term ‘system’ does, however, have multiple meanings, which are not clearly distinguished in the person-oriented literature. I try to disentangle causal interactionism, which describes t

Atomic structure of Yb/Si(100)(2X6): Interrelation between the silicon dimer arrangement and Si 2p photoemission line shape

Combining photoelectron spectroscopy and density-functional theory calculations, we have studied the atomic geometry of Yb/Si(100)(2 X 6) reconstruction and the mechanisms responsible for its stabilization as well as the influence of this reconstruction on Si 2p core-level photoemission. The analysis of measured and calculated surface core-level shifts supports the recently proposed model of the Y

Modelling the effects of management intensification on multiple forest services: a Swedish case study

The study presents a method to evaluate the response of forest ecosystems to increased biomass extraction based on the integrated ecosystem model ForSAFE. It evaluates the effects of residue removal, intensification of thinnings and a shorter rotation period on a forest site in Southern Sweden. The evaluation includes multiple ecosystem indicators for productivity, carbon storage, wood production,

Quantification of cystatin C by time-resolved fluorometry-based immunoassays

Plasma cystatin C is increasingly used as a marker of glomerular filtration rate. Most assays for cystatin C are based on turbidimetric or nephelometric detection and studies of other rapid methods are limited. This study aimed to develop and compare differently configured immunoassays for quantification of plasma cystatin C, using recombinant cystatin C and two cystatin C-specific antibodies. Met

Characterization of the Mechanisms of Drug Release from Polymer-Coated Formulations using Experiments and Modelling

The main objectives of the work presented in this thesis were to develop new experimental methods to improve the understanding of the release mechanism from a coated formulation and to develop new mechanistic models to describe the release process for pellets coated with a semi-permeable film. Another aim was to characterize the release mechanism from a formulation coated with films made of a blen

Nonspecific Chronic Orofacial Pain: Studying Patient Experiences and Perspectives with a Qualitative Approach

Aims: To analyze the nonspecific chronic orofacial pain patient's experience of the pain condition and to gain knowledge on the complexity of the problem. Methods: Fourteen patients (1 I female, 3 male) aged 21 to 77 years were selected among those referred to a specialist clinic. All selected patients agreed to participate. Data were obtained through thematic in-depth interviews that exposed the

Improving photo-stability of conjugated polymer MEH-PPV embedded in solid matrices by purification of the matrix polymer

For single molecule spectroscopy (SMS), molecules under study are usually immobilized in a polymer matrix e. g. poly(methyl methacrylate). We show a very significant improvement of the conjugated polymer MEH-PPV photo-stability and decrease of the luminescence impurities concentration when the matrix is purified. We identify benzoyl peroxide (a common radical initiator) as a possible oxidizing age

White matter hyperintensities and medial temporal lobe atrophy in clinical subtypes of mild cognitive impairment: the DESCRIPA study

Background: Clinical subtypes of mild cognitive impairment (MCI) may represent different underlying aetiologies. Methods: This European, multicentre, memory clinic based study (DESCRIPA) of non-demented subjects investigated whether MCI subtypes have different brain correlates on MRI and whether the relation between subtypes and brain pathology is modified by age. Using visual rating scales, media