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A comparative study of ordinary and mineralised Portland cement clinker from two different production units Part II: Characteristics of the calcium silicates

Portland cement clinkers from two production units were investigated in order to determine the effects of mineralisation on alite and belite; Plant 1: ordinary clinker (P1) and clinker mineralised with CaF2 + CaSO4 (P1M); Plant 2: ordinary clinker (P2) and two clinkers mineralised with CaF2 + CaSO4 (P2m, P2m'). The polymorphism of alite was studied using synchrotron X-ray powder diffraction (XRD),

Ultrafast opto-terahertz photonic crystal modulator

We present an agile optically controlled switch or modulator of terahertz (THz) radiation. The element is based on a one-dimensional photonic crystal with a GaAs wafer inserted in the middle as a defect layer. The THz electric field is enhanced in the photonic structure at the surfaces of the Ga-As wafer. Excitation of the front GaAs surface by ultrashort 8 10 nm laser pulses then leads to an effi

Heat and mass transfer in chicken breasts - effect on PhIP formation

Heterocyclic amines are mutagenic/carcinogenic compounds that are found in cooked meat and fish. These compounds are of concern in the aetiology of human cancer and therefore it is important to minimise their formation during cooking, and their intake. PhIP (2-amino-1-methyl-6-phenylimidazo[4,5-b]-pyridine, CAS no: 105650-23-5) is one heterocyclic amine that is found at high levels in cooked chick

Cadmium accumulation and Salix-based phytoextraction on arable land in Sweden

Cadmium accumulation in arable soils causes concern due to possible direct environmental effects and health risks associated with exposure of humans to cadmium through agricultural products. This paper discusses the problem of cadmium accumulation in Swedish arable land, and evaluates Salix (Salix vinimalis) cultivation as a tool for addressing the problem. It is found that Salix cultivation offer

Alkaline sphingomyelinase: An old enzyme with novel implications.

Alkaline sphingomyelinase (alk-SMase) is present in the intestinal tract and additionally human bile. It hydrolyses sphingomyelin in both intestinal lumen and the mucosal membrane in a specific bile salt dependent manner. The enzyme was discovered 36 years ago but got real attention only in the last decade, when sphingomyelin metabolism was realized to be a source of multiple lipid messengers, and

Changes in biologically active ultraviolet radiation reaching the Earth's surface

Stratospheric ozone levels are near their lowest point since measurements began, so current ultraviolet-B (UV-B) radiation levels are thought to be close to their maximum. Total stratospheric content of ozone-depleting substances is expected to reach a maximum before the year 2000. All other things being equal, the current ozone losses and related UV-B increases should be close to their maximum. I

Task based exposure assessment in ergonomic epidemiology: a study of upper arm elevation in the jobs of machinists, car mechanics, and house painters

Aims: To explore the precision of task based estimates of upper arm elevation in three occupational groups, compared to direct measurements of job exposure. Methods: Male machinists (n = 26), car mechanics ( n = 23), and house painters ( n = 23) were studied. Whole day recordings of upper arm elevation were obtained for four consecutive working days, and associated task information was collected i

Effects of magnesium and glucose, insulin, potassium (GIK) solution on the action potential parameters of guinea-pig atrial muscle

The present paper aims to explore the effects of [Mg2+]o and glucose, insulin and K+ (GIK) on action potential parameters in guinea-pig atrial muscle. Specimens of atrial appendages were taken from guinea-pig hearts. Action potentials were recorded in isolated atrial trabeculae. Resting potential (RP) and action potential duration at 90% repolarization (APD90) were measured with conventional micro

Effect of the number, thickness and washing of socks on the thermal insulation of feet

An effective way to increase the insulation on feet is to add socks. However, the effect of adding new layers on feet has not been studied enough. There is limited data on insulation of socks and their combination with footwear. In this study 4 types of socks with different fabric thickness and 3 types of footwear were tested on a thermal foot model to study the effect of the number, thickness and

Essays on International Health Economics: The Role of Health Insurance in Health Care Financing in Low- and Middle-Income Countries

Popular Abstract in Swedish Denna avhandling i nationalekonomi består av fyra stycken självständiga akademiska arbeten. Syftet med avhandlingen är att studera vilken roll hälsoförsäkringar spelar för den privata finansieringen av hälso- och sjukvården i låg- och mellaninkomstländer. Arbetena studerar både effektivitets- och fördelningsfrågor med hjälp av olika typer av metoder. De enskilda arbetenThe thesis consists of an introductory chapter and four independent research papers, summarized as follows. The introductory chapter discusses the role of economics in international health and the policy contributions of each of the particular papers. In addition, the data and the methods that have been used are discussed. Paper I, entitled Community-based health insurance in low-income countries:

Patch testing with serial dilutions of budesonide, its R and S diastereomers, and potentially cross-reacting substances

BACKGROUND: Budesonide, a marker for corticosteroid allergy, is a 1:1 mixture of 2 diastereomers, the R and S, present in all commercial formulations. Budesonide is said to cross-react with group B substances through the R and S diastereomer and some group D substances only through the S diastereomer. OBJECTIVE: To investigate the cross-reactivity pattern between the R and S diastereomers and 4 po

Impulse noise of different durations

This paper describes a comparison between auditory threshold elevations and morphological cochlear changes evaluated with scanning electron microscopy in order to identify cochlear defects in guinea pigs exposed to impulse noise of varying durations. There was a significant difference in the auditory threshold shifts between animals exposed for 3 and 12 hours. Hair cell loss is generally used as a

Extracting syringe for extraction of phthalate esters in aqueous environmental samples

The use of the extracting syringe (ESy), a fully automated membrane-based extraction technique, for analysis of phthalate esters in complex aqueous samples has been investigated. The ESy, working as an autosampler that combines the extraction process and injection into the gas chromatograph (GC) in one single step, is placed on top of the GC equipped with a flame ionisation detector. The aqueous s