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Shear Behavior of Flexible Polyurethane Foams Under Uniaxial Compression

The mechanisms behind the load building capabilities of a hyperbranched polymer (HBP) in polyurethane (PU) foams have been investigated, using microscopy techniques and mechanical analyses. By broadening the traditional uniaxial compression characterization of PU foams to include combined shear deformations and compression behavior, an apparent Poisson ratio of the foam could be obtained in situ.

Rapid hydrological changes during the Holocene revealed by stable isotope records of lacustrine carbonates from Lake Igelsjon, southern Sweden

A Holocene sediment sequence from Lake Igelsjon, south central Sweden, was studied by stable oxygen- and carbon-isotope analyses of different carbonate components. The deposit, which covers the time-span from ca 11,500 cal BP to the present, was laid down in a small, kettle-hole lake, the hydrological balance of which is presently dominated by groundwater flow. Isotopic records obtained on bulk ca

A Double Helix Metaphor for Use and Usefulness in Informing Systems’

Following the theme of this monograph, this paper discusses a dialectic we perceive to subsist between meaningful use and reflection upon use. This dialectic between experiencing use and reflecting upon experiencing use (or thinking, and thinking about thinking) may be considered in the following way. Each of these elements is subject to change. As reflection triggers change in use, and such chang

Calculation of geomagnetically induced currents in the 400 kV power grid in southern Sweden

Sweden has experienced many geomagnetically induced current (GIC) events in the past, which is obviously due to the high-latitude location of the country. The largest GIC, almost 300 A, was measured in southern Sweden in the earthing lead of a 400 kV transformer neutral during the magnetic storm on 6 April 2000. On 30 October 2003, the city of Malmo at the southern coast suffered from a power blac

Combined use of exhaled nitric oxide and airway hyperresponsiveness in characterizing asthma in a large population survey

The aim of the present study was to see whether measurements of airway hyperresponsiveness (AHR) and nitric oxide (NO) in exhaled air (ENO) either separately or in combination, could differentiate between asthmatics and healthy control subjects in a population based survey. In central Norway 8,571 adolescents participated in a large-scale epidemiological survey (Young Helseundersokelsen i Nord-Tro

Silent and Audible Persistent Ductus Arteriosus: An Angiographic Study.

Persistent ductus arteriosus (PDA) murmurs become silent probably due to the direction of the jet across the ductus arteriosus when entering the pulmonary artery. Out of 15 children with silent PDA, 14 demonstrated a ductal flow not contacting and away from the anterior wall of the main pulmonary artery. In 15 children with a continuous murmur caused by a PDA, 12 exhibited a ductal flow toward and

Resonant double Auger decay in carbon K-shell excitation of CO

We have studied double Auger decay after C 1s→2 photoexcitation in gas phase carbon monoxide. Two distinct processes, namely direct double Auger decay and cascade double Auger decay, are identified and studied in detail using multiple coincidence techniques. Cascade Auger decay is shown to be the overall dominant process. Decay channels involving the dissociation of the molecule followed by autoio

Semi-continuous co-digestion of solid slaughterhouse waste, manure, and fruit and vegetable waste

The potential of semi-continuous mesophilic anaerobic digestion (AD) for the treatment of solid slaughterhouse waste, fruit-vegetable wastes, and manure in a co-digestion process has been experimentally evaluated. A study was made at laboratory scale using four 2 L reactors working semi-continuously at 35 degrees C. The effect of the organic loading rate (OLR) was initially examined (using equal p

Two-photon excitation in fluorescence polarization receptor-ligand binding assay

Fluorescence polarization is one of the most commonly used homogeneous assay principles in drug discovery for screening of potential lead compounds. In this article, the fluorescence polarization technique is combined with 2-photon excitation of fluorescence. Theoretically, the use of 2-photon excitation of fluorescence increases the volumetric sensitivity and polarization contrast of fluorescence

Dosimetric characteristics of 6 and 10 MV unflattened photon beams

Purpose: To determine dosimetric properties of unflattened megavoltage photon beams. Materials and methods: Dosimetric data including depth dose, profiles, output factors and phantom scatter factors from three different beam qualities provided by Elekta Precise linacs, operated with and without flattening filter were examined. Additional measurements of leaf transmission, leakage radiation and sur

Polysaccharide characterization by flow field-flow fractionation-multiangle light scattering: Initial studies of modified starches

Chemically modified starches are commonly used for various purposes. Depending on the type of derivatization, a chemical degradation of the original polymeric structure may occur, resulting in a change of molar mass. It is therefore always of interest to know the molar mass and possibly the conformation of the derivative. Four commercially available hydroxypropyl and hydroxyethyl modified starches

Clonal derivation and characterization of human embryonic stem cell lines

Human embryonic stem cells (hESC) are isolated as clusters of cells from the inner cell mass of blastocysts and thus should formally be considered as heterogeneous cell populations. Homogenous hESC cultures can be obtained through subcloning. Here, we report the clonal derivation and characterization of two new hESC lines from the parental cell line SA002 and the previously clonally derived cell l

Studying the effects of adsorption, recoalescence and fragmentation in a high pressure homogenizer using a dynamic simulation model

The emulsification in a high pressure homogenizer was studied using a dynamic simulation model based on the population balance equation. The model includes fragmentation, recoalescence and adsorption of macromolecular emulsifier and uses a simple flow model in order to link the hydrodynamics in the homogenizer to the three physical processes mentioned above. A computer model offers an interesting

Submicrometer-resolution photoelectron-spectroscopy at MAX Lab

The design of a photoemission microprobe beamline at the MAX laboratory is presented. The beamline will utilize the radiation from a 26 period undulator on the 550-MeV MAX storage ring. The beamline will be capable of providing about 1010 photons/s of monochromatized radiation (bandwidth better than 0.25 eV) in the energy range of 20 to 150 eV focused into a submicrometer focal spot. It will be us

Design of a portable large spectral range grazing incidence instrument

A design of a small size grazing incidence instrument is presented, which offers large spectral range and high resolution without sacrificing luminosity. The instrument is particularly suited for use at synchrotron radiation sources since it can be conveniently attached to existing experiment chambers. The basic idea of the design is the use of fixed mounted gratings of diffent radii and groove de

The effect of high or low dietary calcium on bone and calcium homeostasis in young male rats.

Young male rats (100 g body weight) were fed diets containing varying amounts of calcium. Body weight and bone development were studied together with various endocrine parameters, including blood levels of Ca2+, calcitonin, parathyroid hormone, vitamin D, and gastrin, and the enterochromaffin-like (ECL) cell-related parameters gastric mucosal histidine decarboxylase activity and histamine concentr

Inshore Commercial Fisheries in the Service Economy : Session 1 Small-Scale Fisheries Research - towards sustainable fisheries using a multi-entry perspective

The study frames a traditional industry in transition with the aim to understand the ways in which a work-identity is formed in the service economy along the west coast of Sweden. More specifically, we want to understand how diversified inshore commercial fisheries are discursively established and negotiated as a service enterprising subject in three everyday relationships; authorities, customers