Sökresultat

Filtyp

Din sökning på "*" gav 530349 sökträffar

Diurnal IOP fluctuation: not an independent risk factor for glaucomatous visual field loss in high-risk ocular hypertension.

Purpose: To establish whether intraocular pressure (IOP) fluctuations contribute to the risk of developing glaucoma in patients with high-risk ocular hypertension. Methods: Ninety patients included in the Malmo Ocular Hypertension Study were examined every 3 months with office-hours diurnal tension curves and computerised perimetry. Patients were followed up prospectively for 10 years or until gla

Surface electronic structure study of Au/Si(111) reconstructions: Observation of a crystal-to-glass transition

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 SCREAM

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

Short-term effects of enhanced UV-B and CO2 on lichens at different latitudes

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

Hydrolysis of by-products from cereal kernels for improved ethanol production

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

A Scatter Correction Method for 201-Tl images: A Monte Carlo Investigation

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

Träning ökar benmassan hos barn men bara obetydligt hos vuxna

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

Canonical Bases for Algebraic Computations

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

Numerical simulations of light scattering by red blood cells

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

Investigations of radiative lifetimes in the 3p 5p configuration of neutral silicon

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

A Turbo Code Interleaver Design Criterion Based on the Performance of Iterative Decoding

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 3-D resistivity investigation of a contaminated site at Lernacken, Sweden

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

Increased aortic stiffness in women with type 1 diabetes mellitus is associated with diabetes duration and autonomic nerve function

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

Interstitial laser hyperthermia of a rat liver adenocarcinoma

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