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The alpha-root3xroot3, beta-root3xroot3, and 6x6 surfaces of Au/Si(111) have been studied by angle-resolved photoelectron spectroscopy (ARPES). The alpha-root3xroot3 surface shows four surface state bands, one of which is a dispersing metallic band. Except for one nondispersing band near the Fermi level, the beta-root3xroot3 surface shows surface bands that are similar to those of alpha-root3xroot

A linear distinguishing attack on the stream cipher Scream is proposed. When the keystream is of length 2(98) words, the distinguisher has a detectable advantage. When the keystream length is around 2(120) the advantage is very close to 1. This shows certain weaknesses of Scream. In the process, the paper introduces new general ideas on how to improve the performance of linear distinguishing attac

Interaction effects of UV-B and CO2 on three lichens species, Cladonia arbusculo, Cetraria islandica and Stereocaulon paschale, from two latitudinal sites, 68N and 56N, were studied in a laboratory experiment. The response of the plants was recorded by measuring their chlorophyll fluorescence. All species had a similar response to enhanced UV-B depending on the latitude from which the population c

This work deals with the hydrolysis of lignocellulosic agricultural residues, by means of combined pretreatment and enzymatic hydrolysis, to be used for ethanol production. Four agricultural by-products, i.e. barley husk, wheat bran and the waste streams of a combined starch and ethanol factory, denoted wheat starch fibres and starch-free fibres B, were investigated. The starch in wheat bran and w

The differential operator -(d2/dx2)-(y/x), γ∈R, in one dimension is studied using distribution theory. It is proven that there exists a unique self-adjoint operator corresponding to the differential expression understood in the principle-value sense. Point interactions determined by the singular operator -(d2/dx2)-(y/x)+αδ(x) are studied

Results from the application of a modified dual photopeak window scatter correction method to Monte Carlo simulated Tl-201 emission images are presented. In the Monte Carlo investigation, individual simulations are performed for six radiation emissions of Tl-201. For each emission, point sources of Tl-201 are imaged at various locations in a water-filled elliptical tub phantom using three energy w

Data supporting the notion that exercise during growth built a stronger skeleton is compelling. Exercise during growth, especially during the pre-pubertal years, increases bone mineral density (BMD) and perhaps also bone size, each independently conferring bone strength. In adulthood, exercise at best halts bone loss or increases BMD by a few percentage points, an increase of questionable biologic

This thesis deals with computational methods in algebra, mainly focusing on the concept of Gröbner and SAGBI bases in non-commutative algebras. The material has a natural division into two parts. The first part is a rather extensive treatment of the basic theory of Gröbner bases and SAGBI bases in the non-commutative polynomial ring. The second part is a collection of six papers. In the first pap

The nigrostriatal dopamine (DA) system has an essential role in the selection and control of movement sequences, and its degeneration causes the characteristic motor symptoms of Parkinson's disease. Parkinsonian motor symptoms are alleviated by l-DOPA, but this treatment induces motor fluctuations and dyskinesias (abnormal involuntary movements). Clinical and experimental findings indicate that th

Scattering of electromagnetic waves from a red blood cell is simulated using the finite-difference time-domain method (FDTD), the Rytov approximation and the discrete dipole approximation (DDA). Both FDTD and DDA are full wave methods that give accurate results in a wide range of wavelengths. The Rytov approximation is a much simpler method that is limited to scattering angles within 30/spl deg/ f

Lifetimes for the3S1,3P0, 1, 2 and3D1, 2, 3 states in the 3s23p5p configuration of silicon have been determined using stepwise dye laser excitation and time resolved detection. A comparison is made with theoretical values, calculated using multi-configuration Hartree-Fock wavefunctions. Laser-evaporation was used to produce free silicon atoms by focusing a Nd: YAG laser on a rotating silicon targe

The performance of a turbo code is dependent on two code properties: its distance spectrum and its suitability to be iteratively decoded. Both these properties are influenced by the choice of interleaver used in the turbo encoder. This paper presents an interleaver design criterion that focuses on the performance of iterative decoding, based on the correlation properties of the extrinsic inputs. I

A contaminated site at Lernacken in southern Sweden, formerly used for sludge disposal, was investigated using a 3-D resistivity imaging technique. The data acquisition was carried out using a roll-along technique for 3-D data acquisition that allows using standard multielectrode equipment designed for engineering and environmental applications. The technique allows for the measurement of large tr

AIMS: The increase in risk for cardiovascular complications in diabetic women is even greater than that in diabetic men. We found arterial stiffness to be increased in women, but not in men, with Type 1 diabetes mellitus (DM). The aims of the present study were to evaluate whether the changes in arterial distensibility are influenced by diabetes duration and to evaluate any association between aut

The aim of this study was to compare interstitial laser thermotherapy with excision of a liver tumour. A dimethylhydrazine-induced adenocarcinoma was implanted into the left lateral lobe of the rat liver, and treatment was performed 8 days later. Rats were treated with resection of the tumour-bearing lobe or underwent interstitial laser thermotherapy, which was performed at a steady-state temperat