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Surface phase transition and electronic structure of c(5 root 2 x root 2)R45 degrees-Pb/Cu(100)

The c(5 root 2 x root 2)R45 degrees-Pb/Cu(100) surface phase is investigated by means of angle resolved ultraviolet photoemission and low energy electron diffraction in the temperature range between 300 and 550 K. We identify and characterize a temperature-induced surface phase transition at 440 K from the room temperature e(5 root 2 x root 2) R45 degrees phase to a (root 2 x root 2)R45 degrees st

Structural organisation of prolamellar bodies (PLB) isolated from Zea mays. Parallel TEM, SAXS and absorption spectra measurements on samples subjected to freeze-thaw, reduced pH and high-salt perturbation

Well-organised PLB gives rise to a X-ray diffraction pattern overlaid by a scattering pattern arising from individual tubules within less wellorganised regions of the lattice. TEM and SAXS measurements were used to characterise the structural changes in PLB subjected to perturbation by freeze-thaw, exposure to pH 6.5, or resuspension in high-salt media. Comparison of SAXS patterns measured, before

Essays on R&D and Growth

The purpose of this study is to analyze some aspects of the relationship between R&D and economic growth. In Chapter 2 we analyze how costly imitation may be incorporated into an R&D-driven endogenous growth model. In the model, optimizing firms allocate resources to innovation or imitation. Thus, the extent of technology diffusion through imitation is endogenously determined. Costs of im

Maxillary bone mineral density and its relationship to the bone mineral density of the lumbar spine and hip

Objective. We sought to measure the bone mineral density (BMD) of various regions in the maxilla before implant treatment and to investigate correlations between these values and the BMDs of the spine and hip. Study design. Eighteen patients were examined by means of quantitative computed tomography, and the BMD of the maxillary alveolar ridge was calculated. The same patients also underwent dual-

Influence of enzyme loading and physical parameters on the enzymatic hydrolysis of steam-pretreated softwood

Softwood is an interesting raw material for the production of fuel ethanol as a result of its high content of hexoses, and it has attracted attention especially in the Northern hemisphere. However, the enzymatic hydrolysis of softwood is not sufficiently efficient for the complete conversion of cellulose to glucose. Since an improvement in the glucose yield is of great importance for the overall e

Hydrogen peroxide induces mRNA for tumour necrosis factor alpha in human endothelial cells

Reactive oxygen intermediates are important mediators of inflammation. We investigated if hydrogen peroxide (H2O2) induces tumour necrosis factor alpha (TNFalpha) expression in cultured human cells from umbilical vein endothelium (HUVEC), aortic smooth muscle cells (SMC), peripheral blood mononuclear cells (PBMC), or the cell line Mono Mac 6. Cultures were stimulated with 200 micromol/L H2O2 for 1

Biaxial model for the incidence angle dependence of the optical efficiency of photovoltaic systems with asymmetric reflectors

The optical efficiency of concentrating solar thermal and photovoltaic systems with cylindrical geometries is asymmetrical about the optical axis. Biaxial models, based on projected incidence angles, are often used to estimate the annual performance of asymmetric concentrators. However, the use of projected angles tends to underestimate optical losses in the cover glass. In this work, a biaxial mo

Separation characteristics in dissolved air flotation - pilot and full-scale demonstration

This study presents practical implications for particle separation in Dissolved Air Flotation (DAF). The objectives were to localise where particles are separated from the water phase and to determine what particles, in terms of size, are removed by the DAF-process. Both pilot- and full-scale plants were investigated. Particle sizes were analysed with a light-blocking particle counter and an optic

Monte-Carlo simulation of the charged particle detector used in the NORDBALL gamma-ray spectrometer

The NORDBALL silicon detector array for detecting light charged particles emitted in fusion evaporation reactions was simulated with the Monte-Carlo method. The data from the reaction of 261 MeV Ni-58 ions with Cr-50 nuclei in a 4.8 mg/cm(2) thick target was used to adjust the simulation parameters. Relative population of residual nuclei in the reaction was determined, by comparing the intensities

CD40 expression in uterine tissues: A key regulator of cytokine expression by fibroblasts

CD40 is a cell surface receptor initially discovered on cells of the hemopoietic lineage. Its primary role on immune cells is to enhance their activation and hence their production of cytokines and immunomodulatory molecules. Recently, CD40 has also been detected on human fibroblasts. An emerging view of the fibroblast is that it is far more than a structural cell, being capable of intimate intera

Protein hydration dynamics in solution: a critical survey

The properties of water in biological systems have been studied for well over a century by a wide range of physical techniques, but progress has been slow and erratic. Protein hydration-the perturbation of water structure and dynamics by the protein surface-has been a particularly rich source of controversy and confusion. Our aim here is to critically examine central concepts in the description of

Real-time telediagnosis of radiological images through an asynchronous transfer mode network: the ARTeMeD project

The ARTeMeD project aims to solve problems of interactivity and real-time in teleradiology. It integrates personal multimedia facilities and patient data access in a common platform that allows radiologists to collaborate from remote sites through a suitable communication support. ARTeMeD is based on asynchronous transfer mode (ATM) network technology and an optimized manipulation of medical image

Automatic Reduction Procedures for Chemical Mechanisms in Reactive Systems

Popular Abstract in Swedish En av dagens största utmaningar är de stadigt ökande utsläppen av förorenande avgaser och drivhusgaser. Den största delen av dessa föroreningar kommer från förbränningsanläggningar och fordon. För att kunna minska utsläppen måste man förstå förbränningsprocesserna, och hur man kan kontrollera förbränningen. Utmaningen är att förbränningprocesser är mycket komplexa. Det To deal with complex physical and chemical processes in reactive systems, such as combustion processes, it is necessary to find methods that simplify modelling in such a way that it becomes both more comprehensible and practically useful. In the work reported here a method for automatically reducing chemical reaction mechanisms has been developed for use in computer simulations of various combusti

Relations between thyroid function, hepatic and lipoprotein lipase activities, and plasma lipoprotein concentrations

Lipoprotein concentrations and activities of lipoprotein lipase (LPL) and hepatic lipase (HL) were measured in 70 subjects with thyroid function ranging from overt hypothyroidism over subclinical hypothyroidism and euthyroidism to hyperthyroidism. In parallel with serum T3 (S-T3) concentrations increasing from low in hypothyroidism to high in hyperthyroidism there were gradually higher HL activiti

Comparison of vector finite-difference techniques for modal analysis

We compare a vector finite-difference method that correctly applies the boundary conditions at both horizontal and vertical dielectric interfaces (but not at corners or slanted interfaces) to algorithms that only approximately satisfy these boundary conditions. We find, rather unexpectedly, that for strongly guiding waveguides the boundary conditions imposed at the refractive- index discontinuitie

Methods for the determination in the nanomole range of lipids in liver fine-needle aspiration biopsies

Triglycerides and phospholipids 0.5-2mg (wet weight) of human liver material obtained by the fine-needle aspiration biopsy technique can be estimated after chloroform:methanol extraction by the determination of lipid phosphorus and glyceride glycerol. The methods are based on the colorimetric determination of inorganic phosphate after oxidation of the phospholipids and the enzymatic fluorometric d