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On the internal frost resistance of self-compacting concrete, with and without polypropylene fibres

In this article experimental and numerical studies of internal frost resistance of self-compacting and normal concrete, with and without fibres, are outlined. For this purpose self-compacting concrete with low water-cement ratio was studied, with varying amounts of filler, crystalline or sedimentary, different pouring pressures and different mixing procedure with two ages at the start of testing.

High cyanobiont selectivity of epiphytic lichens in old growth boreal forest of Finland

• Here, cyanobiont selectivity of epiphytic lichen species was examined in an old growth forest area in Finland. • Samples of the eight lichen species were collected from the same aspen (Populus tremula) and adjacent aspens in the same stand. The cyanobionts of these samples were compared with free and symbiotic Nostoc obtained from other habitats and geographic regions. • Our results, based on

The structure of Fe(III) ions in strongly alkaline aqueous solutions from EXAFS and Mossbauer spectroscopy

To establish the structure of ferric ions in strongly alkaline (pH > 13) environments, aqueous NaOH solutions supersaturated with respect to Fe(III) and the solid ferric-hydroxo complex salts precipitating from them have been characterized with a variety of experimental techniques. From UV measurements, in solutions of pH > 13, only one kind of Fe(III)-hydroxo complex species was found to be prese

Fast estimation of spatially dependent temporal trends using Gaussian Markov Random fields

There is a need for efficient methods for estimating trends in spatio-temporal Earth Observation data. A suitable model for such data is a space-varying regression model, where the regression coefficients for the spatial locations are dependent. A second order intrinsic Gaussian Markov Random Field prior is used to specify the spatial covariance structure. Model parameters are estimated using the

Assessment of glioma viability by estimating 201Tl SPET tumour uptake volume

The aim of this study was to develop a quantitative method to assess viable tumour based on post-operative 201Tl single photon emission tomography (SPET). We studied 15 patients with histologically defined highly malignant gliomas in the post-operative phase before initiation of adjuvant treatment. A 201Tl index was calculated in two ways: maximal counts versus mean counts within a region of inter

Bcl-3 and NF kappa B p50-p50 homodimers act as transcriptional repressors in tolerant CD4(+) T cells

The transcriptional events that control T cell tolerance are still poorly understood. To investigate why tolerant T cells fail to produce interleukin (IL)-2, we analyzed the regulation of NFkappaB-mediated transcription in CD4(+) T cells after tolerance induction in vivo. We demonstrate that a predominance of p50-p50 homodimers binding to the IL-2 promoter kappaB site in tolerant T cells correlate

Endogenous Acquisition of Information and the Equity Home Bias

This paper investigates the extent to which differences in information costs can explain the equity home bias puzzle. In a model where information costs are higher for the Foreign asset than for the Home asset, we show that---if cost functions are convex and the assets have identical return characteristics---the expected size of the home bias in terms of differences in expected demands is positive

Latin hypercube sampling for stochastic finite element analysis

A Latin hypercube sampling method, including a reduction of spurious correlation in input data, is suggested for stochastic finite element analysis. This sampling procedure strongly improves the representation of stochastic design parameters compared to a standard Monte Carlo sampling. As the correlation control requires the number of realizations to be larger than the number of stochastic variabl

A sulfophenylated polysulfone as the DMFC electrolyte membrane - an evaluation of methanol permeability and cell performance

A sulfophenylated polysulfone (PSU-sph), carrying 0.8 sulfonic acid units per repeating unit of the polymer, is evaluated as a membrane electrolyte for DMFC applications. The liquid uptake, methanol transport characteristics, electrolyte conductivity, and fuel cell performance are investigated. The methanol transport and DMFC performance results are compared to those of Nafion® 117. The PSU-sph me

Spatial covariation of microbial community composition and polycyclic aromatic hydrocarbon concentration in a creosote-polluted soil

Little is known about the spatial connection between soil microbial community composition and polycyclic aromatic hydrocarbon (PAH) concentration. A spatially explicit survey at a creosote-contaminated site demonstrated that microbial biomass (total concentration of phospholipid fatty acids [PLFAs]) and microbial community composition (PLFA fingerprints) were spatially autocorrelated, mostly withi

Time-frequency characterization of femtosecond extreme ultraviolet pulses.

We present energy-resolved cross-correlation measurements of an extreme ultraviolet (XUV) pulse, generated as the fifth harmonic (15.5 eV) of an intense 80 fs laser pulse centered at 400 nm. Spectrally resolving the cross-correlation signal allows us to characterize the time-dependent frequency of the XUV pulse. We find that the fifth harmonic has a small negative chirp in excess of that predicted

Beyond conventional stroke guidelines - Setting priorities

Background and Purpose - Priorities in the care of stroke patients are often intuitive. An open and translucent priority-setting procedure would benefit patients, professionals, and decision-makers. Prioritization is an innovative part of the new Swedish national stroke guidelines. Methods - Working groups identified diagnostic procedures, interventions and therapies in stroke care, assessed each

Defective chromosome segregation and telomere dysfunction in aggressive Wilms' tumors

Purpose: In many childhood neoplasms, prognostic subgroups have been defined based on specific chromosome changes. In Wilms' tumor (WT), such subclassification has been hampered by the diverse and relatively unspecific pattern of chromosomal imbalances present in these tumors. Unspecific patterns of cytogenetic imbalances in tumors are often caused by mitotic segregation errors due to short dysfun

Implicit associations and social anxiety

The aim of this study was to test whether an Implicit Association Test (IAT) with self- and social anxiety-words is sensitive to differences in trait social anxiety, and to an experimental induction of social anxiety. This was performed in the context of a partial replication of a previous study, in which Mauss et al. (2004) compared high and low trait socially anxious individuals before and after

Effects of liming on ectomycorrhizal fungi infecting Pinus-sylvestris L. 3. Saprophytic growth and host plant infection at different ph values in unsterile humus

Five ectomycorrhizal fungi were studied in relation to the effects of applications of lime and wood ash to the growth substrate. Growth and survival of inoculated fungi in unsterile humus and relative root colonization frequency by inoculated and indigenous ectomycorrhizal fungi were measured. Growth of the fungi was tested in Petri dish systems with humus taken from a field site treated with lime

Testing for anthropogenic influence on fire regime for a 600-year period in the Jaksha area, Komi Republic, East European Russia

In an attempt to quantitatively evaluate the natural versus anthropogenic signal in site fire histories, the statistical relationship between dendrochronologically dated fire events and tree-ring chronologies (deemed to be an independent proxy for climate variation) was analyzed for 14 sites in a 2600-km(2) area of pine-dominated forests in the Komi Republic (East European Russia) over the period