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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

Changes induced in the surface electronic structure of Be(0001) after Si adsorption

A study of effects induced in the Be is core level spectrum and in the surface band structure after Si adsorption on Be(0001) is reported. The changes in the Be is spectrum are quite dramatic. The number of resolvable surface components and the magnitude of the shifts do decrease and the relative intensities of the shifted components are drastically different compared to the clean surface. The sur

Flow cytometry analysis of malignant tumors of the head and neck--differences between two methods in the recognition of aneuploidy

DNA aneuploidy, which reflects changes in nuclear DNA-content, as determined cytometrically is a candidate prognostic factor in squamous cell carcinoma of the head and neck. The aim of this study was to compare two different preparation methods with respect to their use in detecting aneuploid tumor cell populations in malignant tumors of the head and neck. Fresh frozen tumor material was used. The

Problems with cold work

First International Symposium on Problems with cold work at Grand Hotel Saltsjöbaden, Stockholm, Sweden on November 16-20, 1997. Organised by, National Institute for Working Life, Solna, Sweden in co-operation with National Institute of Occupational Safety and Health, Cincinnati, USA; National Institute of Occupational Health, Moscow, Russia; National Institute of Public Health, Tokyo, Japan, unde

Apparent half-lives of hepta- to decabrominated diphenyl ethers in human serum as determined in occupationally exposed workers

The aim of the present study was to model apparent serum half-lives of polybrominated diphenyl ethers (PBDEs) with 7-10 bromine substituents. Workers with occupational exposure to PBDEs have elevated serum levels of PBDEs, but these substances are also found in the general population and are ubiquitous environmental contaminants. The calculations were based on exposure assessments of rubber worker

Zephyr : passive climate controlled repositories : storage facilities for museum, archive and library purposes

This report is the thesis of the research and development project entitled: Development of a Resource Saving Concept for the Establishment of a Climate Suitable for the Storage of Objects Worthy of Preservation in Storerooms at Museums and in Archives. In short: The ZEPHYR project. This work is the result of a research and development project. The aim is to improve the possibilities of using pass

Hybrid Monte Carlo simulations of vertical electronic transitions in acetone in aqueous solution

A simulation of the n -> pi* absorption and the pi -> n fluorescence of acetone in aqueous solution is reported. The model has an explicit solvent representation with an effective ab initio treatment of the solute. The model attempts to balance quantum chemistry, intermolecular interactions and statistical thermodynamics. It includes a non-electrostatic perturbation on the solute which models the

Sensitivity study of the finite element model for wood-framed shear walls

A sensitivity study was performed with a nonlinear elastic finite element model for monotonic analyses of wood-framed shear walls. The objective was to provide information about simplifying a model of wood-framed shear walls with no significant loss in accuracy. The simplifications concern features such as slips in joints between frame members, slips in hold-down connections, and bearing between a

Dampness in buildings as a risk factor for health effects, EUROEXPO: a multidisciplinary review of the literature (1998-2000) on dampness and mite exposure in buildings and health effects

The scientific literature on health effects from dampness in buildings, including mite exposure over the period 1998-2000 has been reviewed by a European group (EUROEXPO) of eight scientists in experience from medicine, epidemiology, toxicology and engineering. Forty studies deemed relevant have been the foundation for the conclusions. Dampness in buildings is a risk factor for health effects amon

Mimicking photosystem II reactions in artificial photosynthesis: Ru(II)-polypyridine photosensitisers linked to tyrosine and manganese electron donors

The paper describes a project aiming at constructing functional mimics of the oxygen evolving complex in photosystem II, coupled to photoinduced charge separation. Biomimetic electron donors, manganese complexes and tyrosine, have been linked to a Ru(II)-polypyridine photosensitiser. Oxidation of the donors by intramolecular electron transfer from the photooxidised Ru(III) complex was demonstrated

An optimal bound on the tail distribution of the number of recurrences of an event in product spaces

Let X-1, X-2,... be independent random variables and a a positive real number. For the sake of illustration, suppose A is the event that Xi+1 +...+ X-j greater than or equal to a for some integers 0 less than or equal to i < j < infinity. For each k greater than or equal to 2 we upper-bound the probability that A occurs k or more times, i.e. that A occurs on k or more disjoint intervals, in terms