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Biodiversity and the Lotka-Volterra theory of species interactions: open systems and the distribution of logarithmic densities

Theoretical interest in the distributions of species abundances observed in ecological communities has focused recently on the results of models that assume all species are identical in their interactions with one another, and rely upon immigration and speciation to promote coexistence. Here we examine a one-trophic level system with generalized species interactions, including species-specific int

Subjective recording of fetal movements. II. Screening of a pregnant population; methodological aspects

1914 women were asked to count fetal movements for 15 minutes every evening from the 28th week of pregnancy until parturition. An individual lowest limit for number of fetal movements was calculated from the first five counts. The women were instructed to contact the maternity ward for fetal evaluation as soon as their count fell below the lowest limit on two consecutive evenings (alarm signal). 7

A note on maximum independent set and related problems on box graphs

A box graph is the intersection graph of orthogonal rectangles in the plane. We show that maximum independent set and minimum vertex cover on box graphs can be solved in subexponential time, more precisely, in time 2(O(rootn log n)), by applying Miller's simple cycle planar separator theorem [J. Comput. System Sci. 32 (1986) 265-279] (in spite of the fact that the input box graph might be strongly

Medicine self-poisoning and the sources of the drugs in Lund, Sweden

The purpose of this study was to investigate the prevalence of toxic agents in attempted and completed suicides. The purpose was also to explore the sources of the drugs taken by suicide attempters. Verbal information on drug intake was collected from 280 suicide attempters during 1987-1990 in the Lund-Orup catchment area. Information on the sources of the drugs was collected from 143 of these att

Very-low-density lipoprotein of uremic patients is a poor substrate for bovine lipoprotein lipase in vitro

Very-low-density lipoprotein (VLDL) from 10 hemodialysis patients and 10 healthy controls was studied with respect to the substrate characteristics for bovine milk lipoprotein lipase (LPL). Compared with the control subjects, the hemodialysis patients had significantly higher serum triglyceride and apolipoprotein B-associated apolipoprotein CIII concentrations (1.03 +/- 0.31 v 1.98 +/- 0.86 mmol/L

Cross-bridge cycling in smooth muscle: a short review

This review is focused on the cross-bridge interaction of the organized contractile system of smooth muscle fibres. By using chemically skinned preparations the different enzymatic reactions of actin-myosin interaction have been associated with mechanical events. A rigor state has been identified in smooth muscle and the binding of ATP causes dissociation of rigor cross-bridges at rates slightly s

Correlation between plasma concentrations of calcitonin gene related peptide and pulmonary pressure in patients with systemic sclerosis.

OBJECTIVE: To examine plasma levels of calcitonin gene related peptide (p-CGRP) in patients with systemic sclerosis (SSc) and pulmonary hypertension (PH). MATERIAL AND METHODS: Twenty nine patients with SSc, 10 with diffuse form, 18 with limited form and one with overlapping systemic lupus erythematosus were examined. Twelve patients displayed normal systolic pulmonary artery pressure (PAPsyst) <

Heavy-resistance training in older Scandinavian men and women: short- and long-term effects on arm and leg muscles

The short- and long-term effects of heavy-resistance training (85% of one-repetition maximum (RM)) on elbow flexion and knee extension dynamic and isokinetic strength and on morphology in the biceps brachii and vastus lateralis muscles were evaluated during 1 year in 35 Scandinavian men and women, aged 70-77 years, 12 of whom formed a control group. After the first 11 weeks of training (n = 23; 3

Modeling and Control of the Paper Machine Drying Section

The topic of this thesis is modeling and control of the last part of the paper machine - the drying section. Paper is dried by letting it pass through a series of steam heated cylinders and the evaporation is thus powered by the latent heat of vaporization of the steam. The moisture in the paper is controlled by adjusting the set point of the steam pressure controllers. There exist several commer

MIMO channel measurements for personal area networks

This paper analyzes MIMO propagation channels for personal area networks. Such channels show important differences to propagation channels in wide-area networks, due to the different environments in which the systems are operated, as well as due to different mobility models, ranges, and presence of humans in the environment, and the impact of the antenna arrangement. We present results from a rece

Self-organized dynamics in spatially structured populations

Self-organization and pattern formation represent the emergence of order in temporal and spatial processes. Self-organization in population ecology is gaining attention due to the recent advances concerning temporal fluctuations in the population size of dispersal-linked subunits. We shall report that spatially structured models of population renewal promote the emergence of a complex power law or

Helicobacter pylori and CagA seropositivity and its association with gastric and oesophageal carcinoma.

Objective. Helicobacter pylori infection is an established risk factor for non-cardia gastric adenocarcinoma. Infection with H. pylori strains harbouring the cagA pathology island may augment this association. H. pylori infection may at the same time reduce the risk for oesophageal carcinoma. However, prospective data on the association between CagA seropositivity and gastric or oesophageal carcin

Continuous heat source model for ground heat storage

The ground volume is penetrated by a duct system for injection and extraction of heat. The heat transfer properties between the ground and such a system is here characterized by a heat transfer length. The heat exchange between the soil and the ducts is represented by a heat source/sink distribution in the storage region.

Absolute cerebral blood flow measured by dynamic susceptibility contrast MRI: a direct comparison with Xe-133 SPECT

Absolute regional cerebral blood flow (CBF) was measured in ten healthy volunteers, using both dynamic susceptibility-contrast (DSC) magnetic resonance imaging (MRI) and Xe-133 SPECT within 4 h. After i.v. injection of Gd-DTPA-BMA (0.3 mmol/kg b.w.), the bolus was monitored with a Simultaneous Dual FLASH pulse sequence (1.5 s/image), providing one slice through brain tissue and a second slice thro

Modification of physicochemical properties of dietary fibre in carrots by mono- and divalent cations

Physicochemical changes of dietary fibre in the presence of NaCl or CaCl2 (0, 100 or 400 mM) during boiling (4 or 25 min) of blanched/frozen carrots were investigated, Addition of NaCl (100 mM) to the boiling water reduced total dietary fibre (TDF) content, due to a reduction of insoluble polymers. Higher concentrations had no further effects. NaCl showed minor effects, on molecular weight distrib