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Preconditioned Conjugate Gradient IAA Spectral Estimation

In this paper, we develop superfast approximative algorithms for the computationally efficient implementation of the recent Iterative Adaptive Approach (IAA) spectral estimate. The proposed methods are based on rewriting the IAA algorithm using suitable Gohberg-Semencul representations, solving the resulting linear systems of equations using the preconditioned conjugate gradient method, where a no

Hyperplane Culling for Stochastic Rasterization

We present two novel culling tests for rasterization of simultaneous depth of field and motion blur. These tests efficiently reduce the set of xyuvt samples that need to be coverage tested within a screen space tile. The first test finds linear bounds in ut - and vt -space using a separating line algorithm. We also derive a hyperplane in xyuvt - space for each triangle edge, and all samples outside

Influence of cell-to-cell variability on spatial pattern formation

Many spatial patterns in biology arise through differentiation of selected cells within a tissue, which is regulated by a genetic network. This is specified by its structure, parameterisation and the noise on its components and reactions. The latter, in particular, is not well examined because it is rather difficult to trace. The authors use suitable local mathematical measures based on the Vorono

Embodied Pedagogical Agents: From Visual Impact to Pedagogical Implications

Embodied pedagogical agents – visually represented, computer generated characters in pedagogical roles, such as virtual instructors, mentors and learning companions – populate the digital society in increasing numbers. They are found in educational programmes from preschool to university, as well as in broader educational contexts in the form of medical counsellors, virtual health coaches, informa

Neuropathological findings and staging in dementia

Dementia is a clinical syndrome with the development of impairment in multiple cognitive functions (including memory), severe enough to interfere with activities of daily living, as the main symptom. There are a large number of disorders that can lead to dementia, and neuropathological examination after death is necessary to determine the underlying cause with certainty. The overall aim of this th

Femtosecond x-ray photoelectron diffraction on gas-phase dibromobenzene molecules

We present time-resolved femtosecond photoelectron momentum images and angular distributions of dissociating, laser-aligned 1,4-dibromobenzene (C6H4Br2) molecules measured in a near-infrared pump, soft-x-ray probe experiment performed at an x-ray free-electron laser. The observed alignment dependence of the bromine 2p photoelectron angular distributions is compared to density functional theory cal

High-performance and self-compacting concrete in house building. Field tests and theoretical studies of possibilities and difficulties

Cast in-situ concrete is the most frequently used materials technology worldwide within production of structural frames in multi-storey residential buildings. In Sweden, this technology dominates the market but is challenged by other competitive production methods. The criticism concerns issues as for instance short slab spans (limited flexibility for future refurbishment), long production times,

Markets for Energy Efficiency - Exploring the new horizons of tradable certificate schemes

This doctoral thesis explores the implications of establishing tradable certificate schemes for improving energy efficiency (so-called ‘Tradable White Certificate’ [TWC] schemes). Carrying out different case studies, a set of complementary evaluation methods is applied in conducting ex-ante and ex-post evaluation studies. To analyse the attributes and complexities of TWC schemes, the thesis focuse

The 'informal sector' and the political economy of development

This paper takes an initial step in integrating insights from two sets of literature which have focused on central aspects of development with unfortunate independence. It highlights politically valuable resources, which are identified in the political economy literature, and shows that the informal sector literature provides ample evidence that these resources in general are (i) scarcely availabl

Tapasin - The star of the show in HLA-I maturation

Human leukocyte antigen class I (HLA-I) molecules are present on the cell surface of all nucleated cells. They bind intracellular peptides and present them to the immune system thus providing a readout to cytotoxic T-cells about the status of a cell. Maturation of the HLA-I molecule includes peptide binding in the endoplasmic reticulum with the assistance of several other proteins collectively cal

Prostate-specific antigen at or before age 50 as a predictor of advanced prostate cancer diagnosed up to 25 years later: A case-control study

Background: Based on a large, representative unscreened cohort from Malmo, Sweden, we have recently reported that a single prostate-specific antigen (PSA) measurement at or before age 50 is a strong predictor of prostate cancer occurring up to 25 years subsequently. We aimed to determine whether this association holds for advanced cancers, defined as clinical stage T3 or higher, or skeletal metast

Reaction mechanism of ammonia oxidation over RuO2(110): A combined theory/experiment approach

Combining state-of-the-art density functional theory (DFT) calculations with high resolution core level shift spectroscopy experiments we explored the reaction mechanism of the ammonia oxidation reaction over RuO2(1 1 0). The high catalytic activity of RuO2(1 1 0) is traced to the low activation energies for the successive hydrogen abstractions of ammonia by on-top O (less than 73 kJ/mol) and the

Willingness and acceptability of cervical cancer screening among HIV positive Nigerian women

Background: The proven benefit of integrating cervical cancer screening programme into HIV care has led to its adoption as a standard of care. However this is not operational in most HIV clinics in Nigeria. Of the various reasons given for non-implementation, none is backed by scientific evidence. This study was conducted to assess the willingness and acceptability of cervical cancer screening amo

Assessment of Fusion Gene Status in Sarcomas Using a Custom Made Fusion Gene Microarray

Sarcomas are relatively rare malignancies and include a large number of histological subgroups. Based on morphology alone, the differential diagnoses of sarcoma subtypes can be challenging, but the identification of specific fusion genes aids correct diagnostication. The presence of individual fusion products are routinely investigated in Pathology labs. However, the methods used are time-consumin

Pearls and pitfalls in neural CGRP immunohistochemistry

This review outlines the pearls and pitfalls of calcitonin-gene related protein (CGRP) immunohistochemistry of the brain. Pearls: In 1985, CGRP was first described in cerebral arteries using immunohistochemistry. Since then, cerebral CGRP (and, using novel antibodies, its receptor components) has been widely scrutinized. Here, we describe the distribution of cerebral CGRP and pay special attention

Triplet Excited State Distortions in a Pyrazolate Bridged Platinum Dimer Measured by X-ray Transient Absorption Spectroscopy.

The excited-state structure of a dinuclear platinum(II) complex with tert-butyl substituted pyrazolate bridging units, [Pt(ppy)(μ-(t)Bu(2)pz)](2) (ppy = 2-phenylpyridine; (t)Bu(2)pz = 3,5-di-tert-butylpyrazolate) is studied by X-ray transient absorption (XTA) spectroscopy to reveal the transient electronic and nuclear geometry. DFT calculations predict that the lowest energy triplet excited state,