We investigate how model populations respond to stochastic harvesting in a stochastic environment. In particular, we show that the effects of variable harvesting on the variance in population density and yield depend critically on the autocorrelation of environmental noise and on whether the endogenous dynamics of the population display over- or undercompensation to density. These factors interact

In this paper, we present a novel method for joint estimation of the fundamental frequency and order of a set of harmonically related sinusoids based on the MUltiple SIgnal Classification (MUSIC) estimation criterion. The presented method, termed HMUSIC, is shown to have an efficient implementation using fast Fourier transforms (FFTs). Furthermore, refined estimates can be obtained using a gradien

Three automatic naming tasks (Wiig & Nielsen, 1999) were administered to 60 normal functioning adults. The mean time required for naming 40 single-dimension (colors, forms, numbers, and letters) and 40 dual dimension stimuli (color-form, color-number, and color letter combinations) were compared in young (17-38 yr.) and older (40-68 yr.) men and women. Analysis of variance for the combined gro

Catalytic metal sites in enzymes frequently have second-sphere carboxylate groups that neutralize the charge of the site and share protons with first-sphere ligands. This gives rise to an ambiguity concerning the position of this proton, which has turned out to be hard to settle with experimental, as well as theoretical, methods. We study three such proton-transfer reactions in two proteins and sh

In many gel applications the swelling and shrinking kinetics are very important, e.g. in controlled/slow release, where the kinetics determine the rate of out-diffusion of the active component, and in gel extraction where the gel is swollen and shrunk several times. In this study swelling kinetics of poly(N-isopropylacrylamide) gel (NiPAAm gel) was determined by monitoring the swelling process usi

Background: Current therapies for antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis are limited by toxicity. Objective: To compare pulse cyclophosphamide with daily oral cyclophosphamide for induction of remission. Design: Randomized, controlled trial. Random assignments were computer-generated; allocation was concealed by faxing centralized treatment assignment to providers at the

A large pedigree with autosomal dominant frontotemporal dementia has been identified. Positional cloning has linked the disease gene to the pericentromeric region of chromosome 3. Clinical, neuropsychological, imaging, pathological and molecular genetic data are presented. The genetic mutation responsible for the disease has not been identified.

The purpose of this study was to propose and evaluate different methods for measuring and reporting exchange gains and losses on corporate monetary items. Focusing on the Swedish experience, the empirical validity of three laws/monetary relationships from economic theory were examined for currencies in the Swedish 'basket' for the period 1974–1981. The basic overall finding of the study was that a

The Sahel belt of Africa has been the focus of intensive scientific research since the 1960s, spurred on by the chronic vulnerability of its population to recurring drought and the threat of long-term land degradation. But satellite sensors have recently shown that much of the region has experienced significant increases in photosynthetic activity since the early 1980s, thus re-energizing long-sta

Zircon grains from nine samples of metavolcanic rocks, gneisses, granitoids and migmatites from the Blekinge Province in southeasternmost Sweden have been dated by U-Pb using ion microprobe. The results suggest that most of the Blekinge bedrock was formed within a narrow time interval of 1.77-1.75 Ga, including the Vastana supracrustal formation and 'coastal gneisses' previously dated to c. 1.70 G

The oceanographic conditions in the high-latitude North Atlantic ocean during the Holocene were reconstructed through analyses of sea surface temperature (SST; alkenone unsaturation ratios) and ice rafting (mineralogy and grain size) from two sediment sequences, one recovered from the Reykjanes Ridge at 59degreesN and the other from the Norwegian Sea at 68degreesN. Comparison of our records to pub

Platelet-derived growth factor-B (PDGFB) is necessary for normal cardiovascular development, but the relative importance of different cellular sources of PDGFB has not been established. Using Cre-lox techniques, we show here that genetic ablation of Pdgfb in endothelial cells leads to impaired recruitment of pericytes to blood vessels. The endothelium-restricted Pdgfb knockout mutants also develop

A car-borne NaI(TI) spectrometric system was used together with a Cs-137 source to obtain realistic data in the search for unshielded and semi-shielded orphan sources. The potassium-stripped counts (PSC) method was used to estimate the influence by the shielding on the detection ability. A reduction of about 5% in the critical distance was obtained for the semi-shielded source. A curve fitting met

BACKGROUND: TNFalpha may contribute to the pathophysiology of airway inflammation. For example, we have recently shown that nasal administration of TNFalpha produces late phase co-appearance of granulocyte and plasma exudation markers on the mucosal surface. The objective of the present study was to examine indices of granulocyte presence and activity in response to intranasal TNFalpha challenge.

The V3 region of the human immunodeficiency virus type 1 envelope protein gp120 constitutes a potential neutralization target, but the oligosaccharide of one conserved N-glycosylation site in this region protects it from neutralizing antibodies. Here, we determined whether N-linked glycans of other gp120 domains were also involved in protection of V3 neutralization epitopes. Two molecular clones o

Two different ethyl(hydroxyethyl) cellulose (EHEC) samples were characterized by size-exclusion chromatography (SEC) with multiangle light scattering (MALS) detection and high-performance anion-exchange chromatography (HPAEC) with pulsed amperometric detection (PAD). The aim of the study was to investigate the molar mass distribution and the heterogeneity of the substituent distribution, factors t

Background/Aims: To build and analyze regression models predicting (1) the long-term cognitive outcome in donepezil-treated patients with Alzheimer's disease, and (2) the short-term (6 months) cognitive impact of treatment depending on cognitive severity at baseline. Methods: The Swedish Alzheimer Treatment Study (SATS) is an open-label, non-randomized, 3-year, multicentre study in a routine clini